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A new strategy for the stereospecific syntheses of C-furanosides

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Chinese Journal of Chemistry 1997年第2期15卷 178-187页

作者： Yang, BH Jiang, JQ Huang, XL wu, hm State Key Laboratory of Bio‐organic and Natural Products Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

This reaction provided an efficient method to synthesize C-furanoside derivatives in high yields and stereospecificity under mild conditions. The cyclization mechanism regarding benzyl group as a leaving group was dis... 详细信息

关键词： C-furanosides benzyl group stereospecific cyclization H-1-H-1 NOESY

27-Ald-triterpenoid saponins from Adina rubella

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Chinese Journal of Chemistry 1997年第5期15卷 431-437页

作者： Fan, GJ He, ZS wu, hm Xu, JF Chinese Acad Sci Shanghai Inst Mat Med Shanghai 200031 Peoples R China Chinese Acad Sci Shanghai Inst Organ Chem State Key Lab Bioorgan & Nat Prod Chem Shanghai 200032 Peoples R China

Four new triterpenoid saponins were isolated from the roots of Adina rubella Hance. They were characterized as adinaic acid 3 beta-O-[alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glucurono-pyranoside-6-O-methyl ester]-28-O-beta-D-glucopyranoside, adinaic acid 3 beta-O-[alpha-L-rhamnopyranosyl(1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glucuronopyranoside-6-O-butyl ester]-28-O-beta-D-glucopyranoside, adinaic acid 3 beta-O-[beta-D-glucopyranosyl(1-->2)-beta-D-glucopyrnaosyl]-(28-->1)-beta-D-glucopyranosyl(1-->6)-beta-D-glucopyranosyl ester, 27-hydroxyursolic acid 3 beta-O-[alpha-L-rhamnopyranosyl (1-->2)-beta-D-glucopyranosyl(1-->2)-beta-D-glucuronopyranoside-6-O-methyl ester]-28-O-beta-D-glycopyranoside. Their structures were elucidated by spectral methods, especially with the aid of 2D NMR techniques. Their complete assignments of the H-1 and C-13 NMR signals were carried out.

关键词： Adina rubella Hance Rubiaceae adinaic acid glycosides 27-ald-terpenoids

Two furano-sesquiterpenes from the South China Sea Sponge Dysidea fragilis

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Chinese Journal of Chemistry 1995年第5期13卷 460-463页

作者： Su, JY Zhong, YL Zeng, LM wu, hm Ma, K ZHONGSHAN UNIV DEPT CHEMCANTON 510275GUANGDONGPEOPLES R CHINA CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSTATE KEY LAB BIOORGAN & NAT PROD CHEMSHANGHAI 200032PEOPLES R CHINA

A new sesquiterpene, ent-furodysin (1), has been isolated from the South China Sea Sponge Dysidea fragilis, along with a known sesqui-terpene, ent-furodysinin (2). The structure and relative stereochemistry of 1 and 2... 详细信息

关键词： furano-sesquiterpenes sponge Dysidea fragilis

Stellarins F and G, two new cyclopeptides from Stellaria yunnanensis

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Chinese Journal of Chemistry 1995年第6期13卷 552-557页

作者： Zhao, YR Wang, XK Zhou, J Cheng, CX Huang, XL wu, hm W CHINA UNIV MED SCI SCH PHARMDEPT MED CHEM NAT PRODCHENGDU 610041SICHUANPEOPLES R CHINA CHINESE ACAD SCI KUNMING INST BOTLAB PHYTOCHEMKUNMING 650204YUNNANPEOPLES R CHINA CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSTATE KEY LAB BIOORGAN CHEM & NAT PRODSHANGHAI 200032PEOPLES R CHINA

In the previous papers, we reported the structural elucidation of stellarins A-E, five new cyclopeptides from the fresh roots of Stellaria yunnanensis Franch. Further chemical study on this plant led to the isolation of two other new cyclopeptide named stellarins F(1) and G(2). By a combination of 2D-NMR, enzymatic degradation and FABMS, their structures were established to by cyclo(Gly-Ala-Gly-Ser-Pro-Trp-Phe-Pro) and cyclo(Gly-Ala-Tyr-Leu-Ala), respectively.

关键词： Stellaria yunnanensis caryophyllaceae cyclopeptides stellarins F and G

Periodic surface structures fabricated by one excimer laser pulse through a silica phase mask grating

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Chinese Science Bulletin 1997年第21期42卷 1787-1792页

作者： Luo, GP wu, hm Wang, M Zhu, SN Lu, YQ Liu, ZG Wei, Y Ming, NB Nanjing Univ Natl Lab Solid State Microstruct Nanjing 210093 Peoples R China

RECENTLY, excimer laser devices, which have higher-energy density output in pulsed ultravio-let (UV) light (193 or 248 nm), have been employed to generate some thin film struc-tures. The principle of this technique, which is also called pulsed laser deposition (PLD)technique, is that the exposed material could be ablated out of the sample by the focusing laserbeam, and redeposit on a substrate to form thin-film structures under certain conditions. Onthe other hand, researchers have obtained high-quality Bragg gratings in photosensitive

关键词： excimer laser pulse phase mask grating periodic surface structures.

Association between high-sensitivity cardiac troponin T and N-terminal pro-brain natriuretic peptide in a community based population

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Chinese Medical Journal 2014年第4期127卷 638-644页

作者： Xu RY Ye P Luo LM Sheng L wu hm Xiao WK Zheng J Wang F Xiao TH Department of Geriatric Cardiology Chinese People&#39 s Liberation Army General Hospital Beijing 100853 China Department of Geriatric Cardiology Navy General Hospital Beijing 100048 China Department of Geriatric Cardiology Chinese People&#39 s Liberation Army General Hospital Beijing 100853 China

Background N-terminal pro-B-type natriuretic peptide （NT-proBNP） and high-sensitivity cardiac troponin T （hs-cTnT） are excellent biomarkers for detecting heart failure and subclinical myocardial ***,it remains unclear whether subclinical myocardial injury is associated with NT-proBNP elevation in a community based *** In a community based study,levels of hs-cTnT and of NT-proBNP were determined in 1 497 participants older than 45 *** lower detection limit of the hs-cTnT assay used in the present study was 0.003 ng/*** association of hs-cTnT levels and NT-proBNP levels was *** When the subjects with undetectable （〈0.003 ng/ml）,intermediate （0.003-0.014 ng/ml）,and elevated （≥0.014 ng/ml） levels of hs-cTnT were compared （r=0.175,P 〈0.001）,a strong association between the hs-cTnT levels and NT-proBNP levels was observed （β=-0.206,P 〈0.001; β=-0.118,P 〈0.001,respectively）.In multivariable analyses,older age and hs-cTnT were positively and independently associated with NT-proBNP levels （β=0.341,P 〈0.001; β=0.143,P 〈0.001,respectively）,and male gender and the levels of eGFR were inversely and independently associated with NT-proBNP *** the subjects with normal or elevated NT-proBNP were analyzed separately,the hs-cTnT level was not an independent predictor for the NT-proBNP level in the normal NT-proBNP group,whereas the hs-cTnT level was the only independent predictor for NT-proBNP level in the elevated NT-proBNP group （β=0.399,P 〈0.01）.Conclusions In this community based population,NT-proBNP elevation was *** addition to female gender and older age,subclinical myocardial injury indicated by the hs-cTnT level was another important factor in NT-proBNP elevation.

关键词： N-terminal pro-brain natriuretic peptide cardiac troponin T myocardial injury

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改善车轮磨损的轮形优化设计

钢铁译文集 1999年第1期 30-36页

作者： wu,hm 张慧

根据目前伦敦地铁的标准轨形，现已设计出一种新的车轮轮形，与现有标准车轮轮形相比，预防新的车轮轮形状更适合轨形。它减少了５０％最大接触应力，降低了２４％磨损等级，而且磨损分布也更加均匀。本文将介绍这种车轮轮形的优化设计... 详细信息

根据目前伦敦地铁的标准轨形，现已设计出一种新的车轮轮形，与现有标准车轮轮形相比，预防新的车轮轮形状更适合轨形。它减少了５０％最大接触应力，降低了２４％磨损等级，而且磨损分布也更加均匀。本文将介绍这种车轮轮形的优化设计过程。

关键词：车轮优化设计轮形磨损铁路

Ballistic performances of the hourglass lattice sandwich structures under high-velocity fragments

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Defence Technology（防务技术） 2024年第1期31卷 312-325页

作者： He-xiang wu Jia Qu Lin-zhi wu Key Laboratory of Advanced Ship Materials and Mechanics College of Aerospace and Civil EngineeringHarbin Engineering UniversityHarbin150001China School of Civil Engineering Northeast Forestry UniversityHarbin150040China

In this paper,the numerical simulation method is used to study the ballistic performances of hourglass lattice sandwich structures with the same mass under the vertical incidence of *** is paid to elucidating the influences of rod cross-section dimensions,structure height,structure layer,and rod inclination angle on the deformation mode,ballistic performances,and ability to change the ballistic direction of *** results show that the ballistic performances of hourglass lattice sandwich structures are mainly affected by their structural *** this respect,structural parameters optimization of the hourglass lattice sandwich structures enable one to effectively improve their ballistic limit velocity and,consequently,ballistic performances.

关键词： Hourglass lattice sandwich structures Ballistic performances high-velocity Finite element analysis

Resilience-incorporated seismic risk assessment of precast concrete frames with“dry”connections

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 403-425页

作者： wu Chenhao Tang Yuchuan Cao Xuyang wu Gang Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Nanjing 211102China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095USA School of Civil Engineering Southeast UniversityNanjing 211102China College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China

A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame(PCF)structures with“dry”connections in terms of their low damage and rapid *** framework integrates various uncertainties in the seismic hazard,fragility,capacity,demand,loss functions,and post-earthquake *** this study,the PCF structures are distinguished from ordinary reinforced concrete frame(RCF)structures by characterizing multiple limit states for the PCF based on its unique damage ***,probabilistic story-wise pushover analyses are performed to yield story-wise capacities for the predefined limit *** the seismic resilience analysis,a step-wise recovery model is proposed to idealize the functionality recovery process,with separate considerations of the repair and non-repair *** recovery model leverages the economic loss and downtime to delineate the stochastic post-earthquake recovery curves for the resilience loss *** such,contingencies in the probabilistic post-earthquake repairs are incorporated and the empirical judgments on the recovery parameters are largely *** proposed framework is demonstrated through a comparative study between two“dry”connected PCFs and one RCF designed as alternative structural systems for a prototype *** results from the risk quantification indicate that the PCFs show reduced loss hazards and lower expected losses relative to the ***,the PCF equipped with energy dissipation devices at the“dry”connections largely reduces the expected economic loss,downtime,and resilience loss by 29%,56%,and 60%,respectively,compared to the RCF.

关键词： precast concrete frame non-emulative precast system seismic resilience seismic risk functional recovery