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Demonstration of Covalent Sidewall Functionalization of Single Wall Carbon Nanotubes by NMR Spectroscopy:Side Chain Length Dependence on the Observation of the Sidewall sp^(3)Carbons

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Nano Research 2008年第1期1卷 72-88页

作者： Liling Zeng Lawrence b.Alemany Christopher L.Edwards Andrew R.barron Richard E.Smalley Institute for Nanoscale Science and technology and Department of Chemistry Rice UniversityHoustonTX 77005USA

Carboxylic acid-functionalized single walled carbon nanotubes(SWNts)prepared via the reaction of an amino acid,NH2(CH2)nCO2H where n=1(glycine,GLY),5(6-aminohexanoic acid,AHA),10(11-aminoundecanoic acid,AUDA),with fl uorinated single walled carbon nanotubes(F-SWNts)have been characterized by MAS 13C NMR *** ease of observing the aliphatic CH2 groups and the resolution of the signal are dependent on the length of the amino acid’s aliphatic *** have proposed that where substituent chains are short(making NMR data collection difficult)chemical modification to extend the chain length should alleviate analysis *** this regard,we have investigated the esterifi cation of the carboxylic acid *** amino acid-functionalized SWNts were esterified with an appropriate alcohol to ensure parity of the overall substituent length,i.e.,GLY-SWNt(C1)+1-dodecanol(C_(12))=DOD-GLY-SWNt(1),AHA-SWNt(C_(5))+1-octanol(C_(8))=OCt-AHA-SWNt(2),and AUDA-SWNt(C_(10))+1-propanol(C_(3))=PRO-AUDA-SWNt(3).the 13C NMR shift for the sp3 nitrogen-substituted carbon atoms of the SWNt sidewall is observed atδ≈75 *** the length of SWNt sidewall functional groups enhances the ability to observe the sidewall sp^(3)*** methylene carbon signal intensity is less attenuated in the dipolar dephasing spectrum of the ester-functionalized SWNts than their associated amino acid derivatives,suggesting more motional freedom of the side chain in the solid *** confi rmation of the dipolar dephasing spectral effects was assisted by the characterization of the ester of AUDA-SWNt with 1,3-propanediol:PPD-AUDA-SWNt(4).

关键词： Single walled carbon nanotube(SWNt) nuclear magnetic resonance(NMR) esterification amino acid functionalization

基于超声影像组学列线图预测侵袭性乳腺癌淋巴血管侵犯的多中心回顾性研究

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国际医学放射学杂志 2024年第2期 248-248页

作者： Y.Du M.J.Cai H.L.Zha b.D.Chen J.Gu M.Q.Zhang 李晓舒

摘要目的开发并验证一种基于超声（US）影像组学的列线图，用于术前预测浸润性乳腺癌（IbC）病人淋巴血管侵袭（LVI）状态。方法回顾性连续纳入来自3个机构的456名

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Fabrication of AA7005/tib2-b4C surface composite by friction stir processing: Evaluation of ballistic behaviour

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Defence technology（防务技术） 2019年第3期15卷 363-368页

作者： Nitinkumar Pol Gaurav Verma R.P.Pandey t.Shanmugasundaram Research and Development Establishment (Engineers) Pune India Department of Metallurgical & Materials Engg. Defence Institute of Advanced Technology Pune India Armament Research and Development Establishment Pune India

the present work aims to enhance the ballistic resistance of AA7005 alloy by incorporating the tib2 and b4C ceramic reinforcement particles. Surface composites with different weight fractions of tib2 and b4C particles were processed by friction stir processing. Micro-hardness and depth of penetration tests were carried out to evaluate the ballistic properties of the surface composites. the surface hardness of the composite was found to be nearly 70 HV higher than base alloy. the depth of penetration of the steel projectile was 20e26mm in the composites as compared to 37mm in the base alloy. ballistic mass efficiency factor of the surface composite was found to be 1.6 times higher than base alloy. this is mainly attributed to the dispersion strengthening from the reinforcement particles.

关键词： Aluminum alloys Metal matrix composite ballistic testing Friction stir processing

In-depth analysis of the influence of bio-silica filler(Didymosphenia geminata frustules)on the properties of Mg matrix composites

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Journal of Magnesium and Alloys 2023年第8期11卷 2853-2871页

作者： Izabela b.Zgłobicka Anna Dobkowska Aleksandra Zielińska Ewa borucinska Mirosław J.Kruszewski RafałZybała tomasz Płociński Joanna Idaszek Jakub Jaroszewicz Krystian Paradowski bogusława Adamczyk-Cieślak Kostiantyn Nikiforow bartosz bucholc WojciechŚwięszkowski Krzysztof J.Kurzydłowski Faculty of Mechanical Engineering Bialystok University of TechnologyWiejska 45C15-351 BialystokPoland Faculty of Materials Science and Engineering Warsaw University of TechnologyWoloska 14102-507 WarsawPoland Lukasiewicz Research Network–Institute of Microelectronics and Photonics Al.Lotnikow 32/4602-668 WarsawPoland Institute of Physical Chemistry Polish Academy of Sciences Kasprzaka 44/5201-224 WarsawPoland Institute of Fundamental technological Research Polish Academy of Sciences Pawinskiego 5B02-106WarsawPoland

A novel metal matrix composites(MMC)with Mg matrix reinforced with natural filler in the form of Didymosphenia geminata frustules(algae with distinctive siliceous shells)are presented in this *** plasma sintering(PPS)was used to manufacture Mg-based composites with 1,5 and 10 vol.%ceramic *** a reference,pure Mg was *** results show that the addition of 1 vol.%Didymosphenia geminata frustules to the Mg matrix increases its corrosion resistance by supporting passivation reactions,and do not affect the morphology of L929 *** of 5 vol.%the filler does not cause cytotoxic effects,but it supports microgalvanic reactions leading to the greater corrosion *** content than 5 vol.%the filler causes significant microgalvanic corrosion,as well as increases cytotoxicity due to the greater micro-galvanic effect of the composites containing 10 and 15 vol.%*** results of contact angle measurements show the hydrophilic character of the investigated materials,with slightly increase in numerical values with addition of amount of ceramic *** addition of Didymosphenia geminata frustules causes changes in a thermo-elastic properties such as mean apparent value of coefficient of thermal expansion(CtE)and thermal conductivity(λ).the addition of siliceous reinforcement resulted in a linear decrease of CtE and reduction in thermal conductivity over the entire temperature *** the increasing addition of Didymosphenia geminata frustules,an increase in strength with a decrease in compressive strain is *** all composites an increase in microhardness was *** results clearly indicate that filler in the form of Didymosphenia geminata frustules may significantly change the most important properties of pure Mg,indicating its wide potential in the application of Mg-based composites with a special focus on biomedical use.

关键词： Metal-matrix composites(MMCs) Pulse plasma sintering(PPS) Ceramic filler Microstructure Properties

A Study of Protein and Glycoprotein Syntheses in Pre-implantation Mouse Embryos Using Mini-2D-Electrophoresis, Video Densitometer Scanning and Computer-Image Analysis

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Science China Chemistry 1993年第1期36卷 39-44页

作者：郑明曹詠清 b.LoftsDepartment of Zoology University of Hong Kong Hong Kong 陈廷汉 Department of Endocrinology and Laboratory of Reproductive biology Institute of Zoology Academia Sinica Beijing 100080 PRC Department of Zoology University of Hong Kong Hong Kong

In the present study, proteins and glycoproteins of mouse embryos at 2-cell,morula and blastocyst stages were *** techniques of 35S-Met incorporation,ConA antiserum-precipitating ConA-binding proteins, mini-2D-electrophoresis, fluorography,video densitometer scanning and the computer-lmage system were used for *** of the investigations indicated that proteins and glycoproteins were synthesized by the embryos in a gradual increase manner from 2-cell to blastocyst. A relatively large amount of glycoproteins was synthesized during the morula and blastocyst *** specific small glycoproteins respectively with molecular weights about 6500 and 9000 and PIs at 5.0 and 6.5 were apparently synthesized in the blastocyst but not in the 2-cell or the morula.

关键词： implantation mouse embryos glyeoproteins mini 2D-electrophoresis computer-image analysis.

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前掠翼气动特性研究

西北工业大学学报 1989年第3期7卷 321-328页

作者：张彬乾 b.Laschka 西北工业大学联邦德国布伦瑞克工业大学

为适应飞机新布局发展的需要,进行了前掠翼空气动力特性的低速实验研究。研究内容包括:单独机翼和翼身组合体的纵横向气动特性、流谱及旋涡特性。研究结果表明:前掠翼具有良好的升阻特性,力矩特性及失速特性,可以提供较大的可用升力和... 详细信息

为适应飞机新布局发展的需要,进行了前掠翼空气动力特性的低速实验研究。研究内容包括:单独机翼和翼身组合体的纵横向气动特性、流谱及旋涡特性。研究结果表明:前掠翼具有良好的升阻特性,力矩特性及失速特性,可以提供较大的可用升力和良好的大迎角大侧滑角机动性。以上优点在翼身组合体上更为明显。实验发现前掠翼后缘出现后缘涡,观察了前掠翼特有的前后缘涡系的发生和发展,分析了产生前后缘涡系的原因及前后缘涡系对气动特性的影响。

关键词：前掠翼气动特性流态旋涡

Malaria Prevalence and Associated Risk Factors among batwa Indigenous People of Kanungu District in Southwestern Uganda: Does “Place” Matter?

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Journal of biosciences and Medicines 2023年第7期11卷 223-251页

作者： Didacus b. Namanya Everd M. bikaitwoha Lea berrang-Ford Arthur Kiconco Agnes Kasede Napyo Faculty of Health Sciences & Ministry of Health Uganda Martyrs University Kampala Uganda Department of Public Health Kabale University Kabale Uganda Priestly International Centre for Climate University of Leeds Leeds United Kingdom Institute for Health and Equity Medical College of Wisconsin Milwaukee USA Uganda Martyrs University Faculty of Health Sciences Kampala Uganda

Introduction: Malaria is an important disease, causing high morbidity and mortality, especially in Sub-Saharan Africa. Measuring malaria prevalence using malaria rapid diagnostic tests (mRDts), particularly among a vulnerable population sub-group, is a vital public health step in discovering effective methods of prevention and control. this study set out to examine the association between “place” and other risk factors with malaria prevalence among batwa Indigenous People (IP). Methods: An analytical cross-sectional study design was implemented. two surveys January 2014 (n = 572) and April 2014 (n = 541) involving interviews and testing for malaria using mRDts were conducted in 10 batwa settlements where a total of 1113 batwa of all ages were surveyed and tested. the data were first compiled in MS Excel and then imported and analyzed using StAtA ver.14. Descriptive statistics, were generated, followed by bivariable and multivariable regression model analysis to establish associations between the predictor and outcome variables with p ≤ 0.05 considered statistically significant. Results: Overall prevalence was 13.94% (n = 146). there is a significant relationship between settlement (place) and malaria prevalence AOR 11.7, 95% CI (1.38 - 98.93), p-value = 0.02. More males 16.97% (n = 84) tested positive compared to females 11.23% (n = 62) but there was no statistically significant association between gender and mRDt (p-value > 0.005). Children less than 5 years registered high prevalence and there was a significant relationship between age and mRDt (p-value ≤ 0.005). Wealth proxy indicators showed no association with prevalence p-value = 0.390. Season had no association with prevalence (p-value = 0.80). However, the proportion of the day spent in the forest/woodlands was significantly associated with malaria prevalence COR 12.83, 95% CI (1.14 - 143.73) p-value = 0.04. Low elevation was significantly associated with malaria prevalence COR 2.42, 95% CI (1.32 - 4.41), p

关键词： batwa Indigenous People Malaria Prevalence Place-Related Lifestyles Season Socio-Demographic Factors Uganda

联氨和过氧化氢对铝酸钠溶液中沉淀氢氧化铝的影响（英文）

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transactions of Nonferrous Metals Society of China 2015年第2期25卷 615-621页

作者： N.K.SAHU C.K.SARANGI b.DASH b.C.tRIPAtHY b.K.SAtPAtHY D.MEYRICK I.N.bHAttACHARYA Academy of Scientific and Innovative Research Institute of Minerals and Materials technology Council of Scientific and Industrial Research National Aluminium Company Chemical and Mathematical Sciences Murdoch University

研究添加联氨和过氧化氢时人工合成铝酸钠溶液中氢氧化铝的结晶行为。添加少量联氨会对氢氧化铝的结晶产生影响,如需获得相同的效果,过氧化氢的用量更多。X射线衍射分析表明生成产物为三水铝石。扫描电镜观察表明,添加联氨时产物为团聚... 详细信息

研究添加联氨和过氧化氢时人工合成铝酸钠溶液中氢氧化铝的结晶行为。添加少量联氨会对氢氧化铝的结晶产生影响,如需获得相同的效果,过氧化氢的用量更多。X射线衍射分析表明生成产物为三水铝石。扫描电镜观察表明,添加联氨时产物为团聚状,而添加过氧化氢时产物为细小弥散颗粒。对有联氨和过氧化氢时存在的结晶机理进行了讨论。

关键词：氢氧化铝联氨过氧化氢铝酸钠结晶

Efficacy of dietary phytase supplementation on laying performance and expression of osteopontin and calbindin genes in eggshell gland

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Animal Nutrition 2018年第1期4卷 52-58页

作者： Divya Shet Jyotirmoy Ghosh Sreeja Ajith Vaibhav b.Awachat Arumbackam V.Elangovan ICAR-National Institute of Animal Nutrition and Physiology Department of biotechnology Jain University Department of Microbiology Jain University

this study was conducted to evaluate the effects of different levels of dietary phytase supplementation in the layer feed on egg production performance,egg shell quality and expression of osteopontin(OPN) and calbindin(CALb1) ***-five White Leghorn layers at 23 weeks of age were randomly divided into 5 groups consisting of a control diet with 0.33% non-phytate phosphorus(NPP) and 4 low phosphorus(P) diets: 2 diets(t1 and t2) with 0.24% NPP t 250 FtU/kg laboratory produced phytase or commercial phytase and another 2 diets(t3 and t4) with 0.16% NPP t 500 FtU/kg laboratory produced phytase or commercial phytase with complete replacement of inorganic *** results indicated that there were no significant differences(P > 0.05) in egg production performance and quality of egg during the first 2 months of ***,in next 2 months,a significant drop in egg production and feed intake was observed in birds fed diets with low P and 500 FtU/kg supplementation of laboratory produced *** gene was up-regulated whereas the CALb1 gene was down regulated in all phytase treatment groups irrespective of the source of *** current data demonstrated that250 FtU/kg supplementation of laboratory produced phytase with 50% less NPP supplementation and500 FtU/kg supplementation of commercial phytase even without NPP in diet can maintain the egg *** up-regulation of OPN and down regulation of CALb1 in egg shell gland in the entire phytase treated group birds irrespective of the source of enzymes is indicative of the changes in P bioavailability at this site.

关键词： Phytase Layer Egg production Gene expression Egg shell