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Designing a Protection Scheme in Micro-Grid Systems with DG Using Central Protection Unite and Multiple Setting Group Protection Relays
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作者 Mostafa I. Saleh Gaber El-Saady +1 位作者 Ali M. Yousef El-Noby A. Ibrahim 《Journal of Power and Energy Engineering》 2024年第9期37-49,共13页
Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this... Distributed generators now is widely used in electrical power networks, in some cases it works seasonally, and some types works at special weather conditions like photo voltaic systems and wind energy, and due to this continuous changes in generation condition, the fault current level in network will be affected, this changes in fault current level will affect in the coordination between protection relays and to keep the coordination at right way, an adaptive protection system is required that can adaptive its setting according to generation changes, the fault current level in each case is evaluated using ETAP software, and the required relay setting in each case is also evaluated using Grey Wolf Optimizer (GWO) algorithm, and to select suitable setting which required in each condition, to select the active setting group of protection relay according to generation capacity, central protection unite can be used, and to improve protection stability and minimizing relays tripping time, a proposed method for selecting suitable backup relay is used, which leads to decrease relays tripping time and increase system stability, output settings for relays in all cases achieved our constrains. 展开更多
关键词 Directional Overcurrent Relay protection Coordination Distributed Generators Central protection Unite Multiple Setting group protection Relay
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Investigation into Protective Groups for Anilino Functionality upon Oxone-Mediated Oxidative Esterification
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作者 Tomoko Mineno Takeya Yamamoto +1 位作者 Tomoya Nobuta Hisao Kansui 《International Journal of Organic Chemistry》 CAS 2023年第1期7-15,共9页
In the course of organic synthesis, particularly for multi-step synthesis or natural product total synthesis, the selection of appropriate protective groups for the intended functionality is crucial in order to achiev... In the course of organic synthesis, particularly for multi-step synthesis or natural product total synthesis, the selection of appropriate protective groups for the intended functionality is crucial in order to achieve chemoselective synthetic goals. The development of many useful protective groups has been reported based on the functionality of the anilino group. Herein, we discuss our study of various protective groups and the processes we used to establish compatibility with anilino functionality via the implementation of Oxone-mediated oxidative esterification in methanol. The results and the details of our experiments are reported herein. 展开更多
关键词 Protective groups Anilino Functionality OXONE ALDEHYDE Oxidative Esterification
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Academic Forum on Protection of Vulnerable Groups' Rights
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作者 QI YANPING & CHEN YIYUAN 《The Journal of Human Rights》 2005年第3期39-39,共1页
On March 19, an academic forum was held in Jinan City, Shandong Province, on protection of vulnerable groups’ rights. Sponsored by the Law School of Shandong University, it gathered some 50 experts from the Central P... On March 19, an academic forum was held in Jinan City, Shandong Province, on protection of vulnerable groups’ rights. Sponsored by the Law School of Shandong University, it gathered some 50 experts from the Central Patty School, Chinese Academy of Social Sciences, China Society for Human Rights Studies, Shandong Higher People’s Court, as well as some research universities in the country. Four subjects were discussed at the forum: definition of vulnerable groups, legal principles for protection of vulnerable groups’ 展开更多
关键词 Academic Forum on protection of Vulnerable groups RIGHTS
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The Development of Human Rights Protection in Cross-border Personality Rights and Tort Conflict Laws
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作者 徐伟功 张亚军 LI Donglin(Translated) 《The Journal of Human Rights》 2023年第6期1319-1346,共28页
Personality rights are basic rights related to human dignity in the concept of human rights protection,and respect for personality rights is the basic prerequisite for safeguarding other human rights.Human rights prot... Personality rights are basic rights related to human dignity in the concept of human rights protection,and respect for personality rights is the basic prerequisite for safeguarding other human rights.Human rights protection exerts a profound impact on the value of legislation and enforcement practices of private international laws in the field of cross-border personality rights infringement in various countries,which is mainly manifested in the integration of substantive justice and the humanistic care concept of protecting the rights of vulnerable groups into formal justice,and expands the development space of human rights protection ideas in cross-border personality rights and tort conflict laws.the diversity of human rights protection values determines that cross-border personality rights infringement may lead to conflicts between personality rights and other basic rights,such as freedom of speech.to reconcile such conflicts,a workable method is to prioritize personality rights protection in accordance with the hierarchy of rights theory in the value judgment of public order reservation or to clarify the limits of the right holder’s tolerance obligation through the limited application of the principle of proportionality.China’s current cross-border personality rights and tort conflict law can optimize the protection of the rights of vulnerable groups by diversifying the options of available legal methods,and establish a balancing mechanism between personality rights and freedom of speech,so as to improve China’s legal protection system for human rights in the field of foreign-related civil and commercial affairs. 展开更多
关键词 human rights protection protection of the rights of vulnerable groups substantive justice personality rights and tort conflict laws
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Synthesis and application of an IL-supported diol as protecting group for aldehydes 被引量:1
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作者 Yue Qin Cai Ye Liu Guo Hua Gao 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第10期1205-1208,共4页
A new IL-supported diol, 1-(2,3-dihydroxypropyl)-3-methylimidazolium hexafluorophosphate has been synthesized and characterized by Fr-IR, ^1H NMR, ^13C NMR and MS (ESI). Its physical properties such as freezing po... A new IL-supported diol, 1-(2,3-dihydroxypropyl)-3-methylimidazolium hexafluorophosphate has been synthesized and characterized by Fr-IR, ^1H NMR, ^13C NMR and MS (ESI). Its physical properties such as freezing point, solubility and specific gravity and thermal stability were determined. Synthetic utilities of the resultant diol as a protecting group for aldehydes were also investigated. 展开更多
关键词 IL-supported diol PREPARATION Characterization Protecting group
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Regioselective protection of 10-deacetylbaccatin Ⅲ and semi-synthesis of paclitaxel
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作者 Zhang Hu Li Li Ou +1 位作者 Guo Lin Zhang Yong Ping Yu 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期130-132,共3页
Semi-synthesis of paclitaxel was achieved in four steps from 10-deacetylbaccatin HI (10-DAB HI). The key steps are the regioselective protection at the hydroxyl group at C-7 of 10-DAB HI, using 1,1′-thiocarbonyldii... Semi-synthesis of paclitaxel was achieved in four steps from 10-deacetylbaccatin HI (10-DAB HI). The key steps are the regioselective protection at the hydroxyl group at C-7 of 10-DAB HI, using 1,1′-thiocarbonyldiimidazole as a selective reagent, and the deprotection of the protected paclitaxel with a mixture of p-toluenesulfonic acid and 0.1 mol/L aqueous hydrochloride. 展开更多
关键词 PACLITAXEL Protecting group 1 1′-Thiocarbonyldiimidazole REGIOSELECTIVE SEMI-SYNTHESIS
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The Compatibility of Groups Used to Protect Phenolic Functionality during Oxone-Mediated Oxidative Esterification
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作者 Tomoko Mineno Yuki Suzuki +2 位作者 Tomoya Nobuta Daiki Takano Hisao Kansui 《Green and Sustainable Chemistry》 CAS 2022年第4期83-90,共8页
Protecting groups often play an essential role in organic synthesis, particularly for multi-step synthesis or natural product total synthesis. Various protecting groups areavailable to mask the vulnerable functionalit... Protecting groups often play an essential role in organic synthesis, particularly for multi-step synthesis or natural product total synthesis. Various protecting groups areavailable to mask the vulnerable functionality;phenolic hydroxy groups are noteworthy examples, but their stability differs when protected. Herein, the compatibility of protective phenolic functionality was investigated with the implementation of indium (III) triflate-catalyzed oxidative esterification using Oxone in methanol. A wide range of protective moieties was selected and subjected to Oxone-mediated oxidative esterification. For example, sulfonates were found to be sufficiently stable and inert whereas acetals were susceptible to reaction conditions. The details of this investigation are provided. 展开更多
关键词 Compatibility Protecting groups Phenolic Functionality OXONE Oxidative Esterification
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Constitutional Values of Protecting Human Rights of Disadvantaged Groups
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作者 TAO BO,Professor at the Liberation Army Foreign Language Institute ZHANG NING,staff reporter 《The Journal of Human Rights》 2009年第1期29-31,共3页
The confrontation between the disadvantaged and advantaged groups is eternal throughout the competition for survival. But the human spiritual world has its humane aspect in addition to competition. The concern for and... The confrontation between the disadvantaged and advantaged groups is eternal throughout the competition for survival. But the human spiritual world has its humane aspect in addition to competition. The concern for and protection of the disadvantaged group is the moral law characteristic of humanity, just as the Universal Declaration of Human Rights says in its Article 1: "All human beings are born free and equal in dignity and rights. 展开更多
关键词 Constitutional Values of Protecting Human Rights of Disadvantaged groups
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The 3,4-dimethoxybenzyl group as solubilizing protective group for the in situ deprotection/deposition of extended aromatic thiolate monolayers
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作者 Adrian Wiesner Sonja Katzbach +3 位作者 Dariusz Bebej Martina Dettenhöfer Michael Zharnikov Andreas Terfort 《Nano Research》 SCIE EI CSCD 2023年第1期1695-1702,共8页
While self-assembled monolayers(SAMs)of aromatic thiolates are frequently used in a wide range of applications,their formation is often hampered by the low solubilities of their precursors.Here we introduce the 3,4-di... While self-assembled monolayers(SAMs)of aromatic thiolates are frequently used in a wide range of applications,their formation is often hampered by the low solubilities of their precursors.Here we introduce the 3,4-dimethoxybenzyl group as a protective group for the thiol moiety,which increases the solubility and stability of the precursor,but becomes cleaved off during monolayer formation,especially at elevated temperature(60°C)and in presence of protons(trifluoroacetic acid).For a series of substituted terphenylthiols as model systems,it could be demonstrated by using ellipsometry,infrared-reflection absorption spectroscopy,and scanning-tunneling microscopy that the resulting SAMs have the same structure and quality as the ones obtained from the respective unprotected thiols.The protective group has the additional advantage to be stable under Pdcatalyzed C–C bond formation reaction conditions,facilitating the syntheses of the respective precursors. 展开更多
关键词 self-assembled monolayers protective group SOLUBILITY scanning-tunneling microscopy infrared-reflection absorption spectroscopy
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Enhancing hydrolytic stability of dynamic imine bonds and polymers in acidic media with internal protecting groups
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作者 Hang Chen Chengzhi Cui +2 位作者 Hebo Ye Hanxun Zou Lei You 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第5期161-165,共5页
Imine bonds are among the most explored building motifs in dynamic chemistry,polymers,and materials,and yet,their acid-resistance remains a longstanding issue.Herein we demonstrate a concept of internal protecting gro... Imine bonds are among the most explored building motifs in dynamic chemistry,polymers,and materials,and yet,their acid-resistance remains a longstanding issue.Herein we demonstrate a concept of internal protecting groups for improving the kinetic stability of dynamic imine bonds and polymers.Systematic examination of structure-reactivity relationship of a series of aldehydes/imines bearing a neighboring carboxyl allowed uncovering of required structural features for dynamically masking imine bonds with cyclic structures.Mechanistic studies indicated that noncovalent interactions along with sterics control the ringchain equilibrium and the stability of imine bonds.The incorporation of internal protecting groups into imine polymers further enabled their controlled stability in acidic media.Moreover,a combination of dynamic covalent network and coordination supramolecular network provided a facile means for the modulation of luminescent and mechanical properties of polymers.The strategies and results reported should be beneficial to molecular assemblies,dynamic polymers,biological delivery,and intelligent materials. 展开更多
关键词 Dynamic covalent chemistry Internal protecting group Kinetic stability Imine bond Dynamic polymer
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WTO贸易报复机制的实施——以利益集团理论为视角 被引量:7
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作者 杜玉琼 《现代法学》 CSSCI 北大核心 2012年第1期161-167,共7页
WTO争端解决机制中的贸易报复机制是WTO最具特色、最具创造性的部分,该机制以法律手段保障裁决或建议的执行,其主要目的是"促使违反义务的成员方遵守WTO义务",国内利益集团有动力促成这一目标的实现。国内利益集团通过向政府... WTO争端解决机制中的贸易报复机制是WTO最具特色、最具创造性的部分,该机制以法律手段保障裁决或建议的执行,其主要目的是"促使违反义务的成员方遵守WTO义务",国内利益集团有动力促成这一目标的实现。国内利益集团通过向政府或政府机构提出他们的利益要求从而影响国家贸易政策的制定;通过对政府施加政治压力从而达到实施报复措施的目的,进而促成败诉方尽快全面地履行WTO争端解决机构的裁决,纠正或取消其违规措施以符合WTO的规定。 展开更多
关键词 争端解决机制 贸易报复机制 利益集团 贸易保护主义
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Synthesis of Boc-Asp(OBzl)-β-Ala-Asp(OBzl)-N(OMe)Me as a Useful Precursor of Aspartyl Peptide Aldehyde Derivatives
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作者 邹晓民 赵宏 +2 位作者 傅翌秋 张欣 徐萍 《Journal of Chinese Pharmaceutical Sciences》 CAS 2003年第3期123-126,共4页
Aim To synthesize the tripepide Weinreb amide Boc Asp(OBzl) β Ala Asp(OBzl) N(OMe)Me (7) as a useful precursor of aspartyl peptide aldehyde derivatives; Methods DCC, IBCF method was used for preparation of ... Aim To synthesize the tripepide Weinreb amide Boc Asp(OBzl) β Ala Asp(OBzl) N(OMe)Me (7) as a useful precursor of aspartyl peptide aldehyde derivatives; Methods DCC, IBCF method was used for preparation of Weinreb amide; N hydroxysuccinimide activated ester was used in peptide synthesis; and Boc as N protecting group of amino acid. Results Boc Asp(OBzl) N(OMe)Me (3), Boc β Ala Asp(OBzl) N(OMe)Me (5), and Boc Asp(OBzl) β Ala Asp(OBzl) N(OMe)Me (7) were synthesized successfully. Conclusion An useful precursor of tripeptide aspartyl aldehydes was synthesized. 展开更多
关键词 Weinreb amide aspartyl peptide aldehyde Boc protecting group activated ester
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后危机时期国际贸易环境变化及其对我国的影响与冲击 被引量:5
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作者 徐梅 《学术交流》 CSSCI 北大核心 2013年第8期119-122,共4页
后危机时期,国际贸易市场复杂化与利益集团化趋势更为显著,以中国为代表的新兴贸易大国和以美国为代表的传统贸易大国之间的矛盾和冲突将持续存在,新兴国家和广大发展中国家在国际贸易组织和国际贸易规则制定及实施中的地位和话语权的... 后危机时期,国际贸易市场复杂化与利益集团化趋势更为显著,以中国为代表的新兴贸易大国和以美国为代表的传统贸易大国之间的矛盾和冲突将持续存在,新兴国家和广大发展中国家在国际贸易组织和国际贸易规则制定及实施中的地位和话语权的上升趋势更为明显。国际商品与服务出口市场规模扩大从需要方面为我国贸易发展创造了条件,国际贸易与投资一体化与便利化发展则为中国对外贸易与投资创造了技术与制度条件。新兴贸易方式、新兴贸易商品的出现对我国现有贸易方式、传统商品贸易与传统服务贸易造成冲击,传统贸易保护主义与新贸易保护主义相互融合演化。我国仍然需要大力推动"引进来、走出去"外向型经济发展战略,提高防范国际经济风险的能力。 展开更多
关键词 后危机时期 国际贸易环境 利益集团化 贸易摩擦 新贸易保护主义
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特朗普政府贸易保护主义的原因分析——基于双层次博弈理论的视角 被引量:3
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作者 刘向丽 黄旭 《日本研究》 2018年第2期21-30,共10页
特朗普政府的贸易保护主义给美国的主要贸易伙伴带来了诸多挑战,也给国际贸易发展带来了深远的影响。探究其背后的原因,有助于各国采取更加有效的应对措施。双层次博弈理论为这一问题提供了全新的视角,即国内和国际的双层次博弈是特朗... 特朗普政府的贸易保护主义给美国的主要贸易伙伴带来了诸多挑战,也给国际贸易发展带来了深远的影响。探究其背后的原因,有助于各国采取更加有效的应对措施。双层次博弈理论为这一问题提供了全新的视角,即国内和国际的双层次博弈是特朗普政府的贸易保护主义的主要动因,应对贸易保护也应从国内和国际这两个层次的博弈及其互动着手。 展开更多
关键词 贸易保护主义 双层次博弈 利益集团
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可重复使用的丙磺酸功能化纳米结构SBA-15上醇和酚与六甲基二硅氮烷的硅烷化反应(英文) 被引量:2
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作者 Daryoush ZAREYEE Rezvaneh ASGHARI Mohammad A. KHALILZADEH 《催化学报》 SCIE EI CAS CSCD 北大核心 2011年第12期1864-1868,共5页
Various alcohols and phenols were trimethylsilylated in excellent yields using hexamethyldisilazane in the presence of catalytic amounts of environmentally friendly, hydrophobic, highly thermal stable, and completely ... Various alcohols and phenols were trimethylsilylated in excellent yields using hexamethyldisilazane in the presence of catalytic amounts of environmentally friendly, hydrophobic, highly thermal stable, and completely heterogeneous sulfonic acid functionalized mesostructured SBA-15 in dichloromethane at ambient temperature. Primary, bulky secondary, tertiary, and phenolic hydroxyl functional groups were transformed to the corresponding trimethylsilyl ethers in excellent yields. The simple experimental procedure was accompanied by easy recovery and the catalyst was reusable (at least 18 reaction cycles); these are attractive features of this protocol. 展开更多
关键词 reusable heterogeneous catalyst solid sulfonic acid SBA-15 protecting group SILYLATION HEXAMETHYLDISILAZANE
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为什么关税保护比汇率低估更为常见? 被引量:1
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作者 大卫A.斯坦伯格 王宇 《金融发展研究》 北大核心 2018年第2期58-60,共3页
汇率低估与关税保护具有相似的经济效果,而且本币汇率低估可以使本国企业在国际市场上更具竞争优势,但是多数国家都选择了汇率高估政策。这是因为关税保护政策作为更精准的保护主义工具,可以选择性地实施,不会增大企业成本,更为权势利... 汇率低估与关税保护具有相似的经济效果,而且本币汇率低估可以使本国企业在国际市场上更具竞争优势,但是多数国家都选择了汇率高估政策。这是因为关税保护政策作为更精准的保护主义工具,可以选择性地实施,不会增大企业成本,更为权势利益集团偏好;而汇率低估政策作为普惠性的保护主义工具,较为迟钝而且有可能增加企业成本,因此无法得到更多的使用。 展开更多
关键词 保护主义 对外贸易 权势利益集团
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Selective monotetrahydropyranylation of symmetrical diols using P_20_5/Si0_2 under solvent-free conditions and their depyranylation
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作者 Hossein Eshghi Mohammad Rahimizadeh Sattar Saberi 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第9期1063-1067,共5页
Selective protection of one of the hydroxyl group in 1, n-symmetrical diols is achieved by P2O5/SiO2-catalyzed reaction of the diol with dihydropyran under solvent-free conditions at room temperature. This selective p... Selective protection of one of the hydroxyl group in 1, n-symmetrical diols is achieved by P2O5/SiO2-catalyzed reaction of the diol with dihydropyran under solvent-free conditions at room temperature. This selective protection is simple and it occurred under economically cheap conditions in high yield. The deprotected diol is simply obtained by refluxing of this compound in methanol using the same catalyst without any byproduct formation or additional purifications. 展开更多
关键词 Heterogeneous catalyst P2O5/SiO2 Monotetrahydropyranylation Protecting group Symmetrical diols
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A NEW POLYMER-BOUND 1,2-DIOL AS A PROTECTING AGENT FOR SYMMETRICAL DIALDEHYDE
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作者 任启生 黄文强 +1 位作者 赵芬芝 何炳林 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第4期346-353,共8页
A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chl... A novel polymer-bound 1,2-diol, 3-polystyrylsulfonyl-1,2-propanediol (6) had been prepared by the reaction of sodium polystyrylsulfinate with allyl bromide, followed by oxidation and. hydrolysis or directly with 3-chloro-1,2-propanediol in the presence of a phase transfer catalyst, n-tetrabutylammonium iodide. The capacity of resin 6 for terephthaidehyde reached 1.43 mmol/g. The aldehydic groups attached to polymer 6 reacted with hydroxylamine hydrochloride or reduced by sodium borohydride giving p-formylbenzaldoxime (yield: 89%)and p-formyl-benzalcohol (yield: 734%), respectively. The high yields of these polymer-supported reactions showed that the polymer 6 possessed the effective isolation of its reactive sites. 展开更多
关键词 3-polystyrylsulfonyl-1 2 - propanediol polymer-supported protecting group solid - phase organic synthesis cleavage of aldol linkages
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MOHURD: 10 Cities as the First Group of Pilot Cities for Historic Building Protection
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作者 Qian Fang 《China City Planning Review》 CSCD 2018年第1期4-4,共1页
In order to fully practice the spirit of the 19th CPC National Congress,enhance the protection and inheritance of cultural heritage,and fully exert the utilization value of historic building,the Ministry of Housing an... In order to fully practice the spirit of the 19th CPC National Congress,enhance the protection and inheritance of cultural heritage,and fully exert the utilization value of historic building,the Ministry of Housing and Urban-Rural Development(MOHURD)recently released the list of the first group of pilot cities for historic building protection,which include:Beijing,Guangzhou,Suzhou,Yangzhou, 展开更多
关键词 MOHURD Cities as the First group of Pilot Cities for Historic Building protection
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Chemical Synthesis of a Key Precursor Relevant to the Tetrasaccharide Repeating Unit from Treponema medium ATCC 700293
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作者 Wenbin Sun Guangzong Tian +4 位作者 Meiru Ding Chunjun Qin Xiaopeng Zou Jing Hu Jian Yin 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2024年第14期1615-1622,共8页
Treponema is a Gram-negative anaerobic bacterium,among which the pathogenic Treponema can cause various diseases,such as venereal syphilis(Treponema pallidum),yaws(Treponema carateum),and oral diseases(Treponema denti... Treponema is a Gram-negative anaerobic bacterium,among which the pathogenic Treponema can cause various diseases,such as venereal syphilis(Treponema pallidum),yaws(Treponema carateum),and oral diseases(Treponema denticola and Treponema medium).Although different from conventional lipopolysaccharides,the extracellular glycoconjugate of Treponema may still be a potential antigen and provide a candidate for vaccine development.Hence,we completed the first chemical synthesis of Treponema medium ATCC 700293 tetrasaccharide precursor containing L-ornithine(L-Orn)and D-aspartic acid(D-Asp)derivatives.The efficiency of non-reducing end disaccharide formation has been improved by optimizing the assembly of the protecting groups in the donors and acceptors.Our[3+1]glycosylation strategy attempted to reduce the length of the acceptor to increase the nucleophilicity of the hydroxyl group,thereby improving the efficiency of synthesizing the target tetrasaccharide.The L-Orn derivative was introduced at the final stage due to its influence on the glycosylation stereospecificity and efficiency.Therefore,the successful introduction of two amino acid derivatives and the synthesis of a tetrasaccharide precursor with complex functional-group modifications have provided valuable insights for synthesizing other complex bacterial glycans. 展开更多
关键词 Glycosylation Total synthesis Treponema medium ATCC 700293 Tetrasaccharide precursor Protecting group OLIGOSACCHARIDES Regioselectivity Neighboring-group effects
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