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Mid-infrared Period-Luminosity Relations of Gaia DR3 Long Period Variables

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Research in Astronomy and Astrophysics 2024年第7期24卷 56-70页

作者： Xiaohan c.en Xiaodian c.en Licai Deng Shu Wang tianlu c.en Department of Physics College of ScienceTibet UniversityLhasa 850000China Key Laboratory of cosmic Rays(Tibet University) Ministry of EducationLhasa 850000China cAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sc.ence University of the Chinese Academy of SciencesBeijing 100049China Department of Astronomy China West Normal UniversityNanchong 637009China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China

Long period variable(LPV)stars are very promising distance indicators in the infrared *** selected asymptotic giant branch(AGB)stars in the Large and Small Magellanic cloud(LMc and SMc)from the Gaia Data Release 3 LPV catalog,and classified them into oxygen-rich(O-rich)and carbon-rich(c-rich)AGB *** the Wide-field Infrared Survey Explorer database,we determined the W1-and W2-band period-luminosity relations(PLRs)for each pulsation-mode sequence of AGB *** dispersion of the PLRs of O-rich AGB stars in sequences c'and c is relatively small,around 0.14 *** PLRs of LMc and SMc are consistent in each *** the W2 band,the PLR of large-amplitude c-rich AGB stars is steeper than that of small-amplitude c-rich AGB stars,due to their more circumstellar *** two methods,we find that some PLR sequences of O-rich AGB stars in the LMc are dependent on *** coeffic.ents of the metallicity effect areβ=-0.533±0.213 mag dex~1andβ=-0.767±0.158 mag dex~1for sequence c in W1 and W2 bands,*** significance of the metallicity effect in W1 band for the four sequences is 2.2-3.5σ.Both of these imply that distance measurements using O-rich Mira may need to take the metallicity effect into account.

关键词： stars variables general-stars distances-infrared stars

Substrate specificity of the cypemycin decarboxylase cypD

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Synthetic and Systems Biotechnology 2018年第3期3卷 159-162页

作者： Wei Ding tianlu Mo Dhanaraju Mandalapu Qi Zhang Department of chemistry Fudan UniversityShanghai200433China

The linaridin antibiotic cypemycin is a ribosomal synthesized and post-translationally modified peptide(RiPP)that possesses potent activity against mouse leukemia *** peptide natural product contains an S-[(Z)-2-aminovinyl]-D-cysteine(Avicys)moiety in the *** of Avicys moiety requires an oxidative decarboxylation of the c-terminal cys of the precursor peptide cypA,and this process is catalyzed by a flavin-containing protein *** this work,we tested cypD substrate specificity with a series of synthetic *** show that most of the N-terminal sequence of cypA is not required for cypD activity,and the cterminal three residues serve as the minimal structural element for enzyme *** also show that cypD tolerates various substrates with modified c-termini,allowing for the generation of four novel cypemycin variants with modified Avicys moiety by site direct mutagenesis of the precursor peptide *** study demonstrates the relaxed substrate specificity of cypD and lays a foundation for future bioengineering of Avicys-containing natural products.

关键词： moiety oxidative relaxed

Mesoporous H-ZSM-5 nanocrystals with programmable number of acid sites as ＂solid ligands＂ to activate Pd nanoparticles for c-c coupling reactions

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Nano Research 2018年第2期11卷 874-881页

作者： Wenyu Ke tianlu cui Qiuying Yu Mengying Wang Libing Lv Honghui Wang Zhidong Jiang XinhHao Li Jiesheng c.en School of chemistry and chemical engineering Shanghai Jiao Tong University Shanghai china

In this work, we described a proof-of-concept method to promote the activity and selectivity of Pd nanoparticles for heterogeneous catalysis （exemplified by c-c coupling reactions） by using acid sites within a zeolite framework. The Pd nanoparticles were encapsulated inside the crystalline walls of mesoporous H-ZSM-5 leading to hybrid samples （denoted as Pd@mZ-x-H） with controlled number of acid sites. A linear relationship between the number of acid sites of the zeolite nanocrystals and the catalytic activities of the Pd nanoparticles in organic reactions was established. Moreover, the shape-dependent selectivity of Pd@mZ-x-H was not sacrificed when the final activity was enhanced.

关键词： Brgnsted acidity palladium HZSM-5 mesopores Suzuki coupling

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个性化三维人体模型快速建模方法

计算机辅助设计与图形学学报 2005年第10期17卷 2191-2195页

作者：毛天露王兆其中国科学院计算技术研究所数字化技术研究室

采用模型重用的思想,通过输入21个人体测量学参数对标准人体模型进行编辑,实时获得相应体型的个性化三维人体模型.该方法使得编辑过程能够实时完成;生成的人体模型可以方便地驱动;精选的21个人体测量学参数覆盖了人体各处的细节,能够比... 详细信息

采用模型重用的思想,通过输入21个人体测量学参数对标准人体模型进行编辑,实时获得相应体型的个性化三维人体模型.该方法使得编辑过程能够实时完成;生成的人体模型可以方便地驱动;精选的21个人体测量学参数覆盖了人体各处的细节,能够比较完整地描述人体的外形特征,满足对人体模型个性化的需求.

关键词：三维人体模型定制人体测量学

多民族国家的国家认同建设:价值、困境与出路

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西北民族大学学报（哲学社会科学版） 2021年第3期 30-37页

作者：於天禄清华大学高校德育研究中心北京100084 清华大学马克思主义学院北京100084

作为政治一体化过程的核心要素,国家认同建设反映着多民族国家的政治整合能力、社会治理能力和国家濡化能力,其成败得失关乎国家治理能力的现代化程度和水平。当今世界,多民族国家的国家认同建设普遍面临诸多挑战,如民族异质政策与村社... 详细信息

作为政治一体化过程的核心要素,国家认同建设反映着多民族国家的政治整合能力、社会治理能力和国家濡化能力,其成败得失关乎国家治理能力的现代化程度和水平。当今世界,多民族国家的国家认同建设普遍面临诸多挑战,如民族异质政策与村社政治对国家认同的消解、现代化进程中公民教育与身份识别的矛盾、恐怖主义与极端民族主义对国家认同的撕裂、全球化对边疆地区政治安全的新考验等,其中新旧矛盾相互交织、传统与非传统问题相互复合、不同类型考验相互叠加。为了应对各种挑战,多民族国家需要进行持续的政治整合,在合理把握民族认同和国家认同内在张力的前提下,以公民教育为基础促进国家主体意识提升,理顺国家、政府和执政党认同的逻辑关系,夯实多元一体基础,构建民族共同体。新时代中国国家认同建设的前景在于进一步完善国家治理的体制机制,充分发挥中国特色社会主义制度优势,铸牢中华民族共同体意识,构建凝聚力更强的中华民族命运共同体。

关键词：多民族国家国家认同国家治理现代化民族共同体公民教育

Taxonomic studies of the genus Didea Macquart(Diptera:Syrphidae) with description of a new species from china

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entomotaxonomia 2014年第4期36卷 293-299页

作者：霍科科王天录陕西理工学院生物科学与工程学院陕西汉中723000 陕西理工学院陕西资源生物重点实验室陕西汉中723000 山西省中条山国有林管理局山西侯马043003

We describe a new species in the genus Didea Macquart from china： Didea zhongtiaoshanensis ***. The new species is similar to Didea fasciata Macquart, but differs from the latter by tergite 5 and abdominal sternites. Type specimens are deposited in the Museum of Animals and Botany, Shaanxi University of Technology. A key to chinese species in the genus Didea is offered.

关键词： cyclorrhapha Syrphoidea taxonomy key

Regioselective Benzoylation of Diols,Triols and Tetraols Arrays in carbohydrates

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Regioselective Benzoylation of Diols,Triols and Tetraols Arr...

邻甲酚酞甲醛缩合物及其纤维素膜的pH敏感性

中国化学会第三届全国糖化学会议

作者： Tong Li tianlu Li Richard R.Schmidt Peng Peng National Glyc.engineering Research center Shandong University

Effic.ent strategies and powerful linkage procedures for accessing complex oligosaccharides and glycoconjugates of biological significance have been *** overcome some difficulties of tedious protection-deprotection protocols,we are searching for direct protection methods targeting a specific hydroxy group,thus permitting a more effic.ent preparation of proper glycosyl building blocks for the oligosaccharide *** the present study,cyanide was envisaged to be capable of differentiating between differently positioned hydroxy ***,with 1,2-cis-diols,having an equatorial and an axial hydroxy group,the thermodynamically unfavorable axial O-acylation product was highly regioselectively formed by benzoyl cyanide or acetyl cyanide as acylating agent and DMAP as catalyst at-78 o c;acyl migration was not observed under these *** phenomenon was verified with 3,4-O-unproteced galacto-and fucopyranosides and 2,3-O-unprotected *** this cyanide effect was used in series of oligosaccharides synthesis.

关键词：

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高分子学报 2006年第3期16卷 432-436页

作者：刘志宏刘俊峰陈天禄中国科学院长春应用化学研究所高分子物理与化学国家重点实验室武汉理工大学材料科学与工程学院武汉430070

介绍了一种制备pH值致变色的纤维素膜材料的新方法,其关键技术在于首先将邻甲酚酞与甲醛反应生成邻甲酚酞甲醛低分子量缩合物(cPF),然后再沿用物理“包埋”的方法将其固定在二醋酸纤维素膜中.最后,放入0.1mol LNaOH溶液中水解24h,以增... 详细信息

介绍了一种制备pH值致变色的纤维素膜材料的新方法,其关键技术在于首先将邻甲酚酞与甲醛反应生成邻甲酚酞甲醛低分子量缩合物(cPF),然后再沿用物理“包埋”的方法将其固定在二醋酸纤维素膜中.最后,放入0.1mol LNaOH溶液中水解24h,以增加亲水性,减少响应时间,得到的是一种固定有cPF的水解二醋酸纤维素膜(cPF HcDA).测试表明该膜在pH=8.0～13.0范围内具有很好的pH值致变色性能;平衡响应时间快,约为2～30s;在碱液中贮存6个月后,吸光度损失仅为5%,长期稳定性好.该膜可以用作pH值光纤传感膜材料和重复使用的pH值指示材料,以替代传统的小分子酚酞及一次性的酚酞指示试纸.

关键词：邻甲酚酞甲醛纤维素膜 pH值敏感材料

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储运含油污泥慢速热解特性分析

化工学报 2017年第3期68卷 1138-1145页

作者：王君刘天璐黄群星池涌马增益浙江大学热能工程研究所能源清洁利用国家重点实验室浙江杭州310027

采用精确控温的固定床反应装置研究了罐底油泥和清罐油泥在不同升温速率下热解产物特性。结果发现当升温速率为5℃·min^(-1)和2℃·min^(-1)时,两种油泥样品的油品回收率均高于65%。提高升温速率有利于促进气相产物的生成,同时得到的... 详细信息

采用精确控温的固定床反应装置研究了罐底油泥和清罐油泥在不同升温速率下热解产物特性。结果发现当升温速率为5℃·min^(-1)和2℃·min^(-1)时,两种油泥样品的油品回收率均高于65%。提高升温速率有利于促进气相产物的生成,同时得到的油相产物中环状有机物含量提高而链状有机物含量减少,这说明提高升温速率有助于c—H键断裂和环化反应的发生。借助于TG分析和Doyle方程得到两种油泥的热解反应动力学参数。发现随着升温速率加快,表观反应活化能增大了20%~37%。

关键词：含油污泥慢速热解升温速率模型动力学参数