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飞机尾流控制的SPIV实验研究

飞机尾流控制的SPIV实验研究

Proximate Composition, Mineral and Vitamin Content of Some Wild Plants Used as Spices in Cameroon

第七届全国实验流体力学学术会议

作者：黄烁桥申功炘 Robert Konrath carl F.v.Carmer Kompenhans Jürgen 航空工程与科学学院流体所北京航空航天大学 Institute of Aerodynamics and Flow Technology Germany Aerospace Center(DLR)GottingenGermany

利用简化的飞机模型,通过改变尾翼的迎角及展弦比,试图建立一种能加速自我消亡的尾流涡系统。本实验在拖曳水槽中进行,运用SPIV系统进行测量,获得了一系列空间切面的2d/3C数据,给出两种不同尾翼情况下的SPIV观测结果,并与无尾翼情况作... 详细信息

利用简化的飞机模型,通过改变尾翼的迎角及展弦比,试图建立一种能加速自我消亡的尾流涡系统。本实验在拖曳水槽中进行,运用SPIV系统进行测量,获得了一系列空间切面的2d/3C数据,给出两种不同尾翼情况下的SPIV观测结果,并与无尾翼情况作了对比:若没有尾翼,翼尖涡能单独地存在很长时间,而如果选用合适的尾翼设置,由于尾翼涡和翼尖涡相互作用触发出的Rayleigh-Ludwieg不稳定性(The Rayleigh-Ludwieg instability),尾迹涡的涡核可以在飞机下游约35个展长位置处就破裂掉;另外,为了有效地使尾迹涡破裂,必须使Rayleigh-Ludwieg不稳定性的"触发"发生在翼尖涡完全发展后,触发时间的控制可通过调整尾翼迎角及展弦比来实现。

关键词：尾流涡 SPIV Rayleigh-Ludwieg不稳定性

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Food and Nutrition Sciences 2012年第4期3卷 423-432页

作者： Armand Abdou Bouba Nicolas Yanou Njintang Harquin Simplice Foyet Joel Scher didier Montet carl Moses F. Mbofung department of Agriculture Livestock and By-Products University of Maroua Maroua Cameroon department of Biological Sciences Faculty of Science University of Ngaoundere Ngaoundere Cameroon department of Food Science and Nutrition University of Ngaoundere Ngaoundere Cameroon Laboratoire d’Ingénierie et des Biomolécules (LiBio) Nancy-Université Nancy France

The aim of this work was to contribute to our knowledge of the proximate composition, mineral and vitamin content of 20 edible wild plants used as spices in Cameroon. The plant species were collected from 3 different markets in the West Region of Cameroon and analysed for their content of crude proteins, and lipid, ash, moisture, available sugars, total phenols, carotenoids, minerals (Ca, Zn, K, Na, Mg, Al, Mn, Cu and Se), and vitamins (A, E and C) as well as for their pH and colour. Results revealed that all the plants were low in moisture (7.7 to 10.5 g/100 g) but high in ash content (7.7 to 10.5 g/100 g). Hua gabonii (bark) (1594.5 mg/100 g) was relative source of calcium, Echinops giganteus (206.4 mg/100 g) exhibited the highest level of iron and Scorodophleus zenkeri (310.0 μg/100 g) the highest level of selenium. Generally all the plants were found to contain low levels of Zn, Cu and Mg. Wide variations were observed for the pro- teins and available sugars among the samples. The lipid content of some of the plants were surprisingly relatively high as was the case with Monodora myristica (53.4 g/100 g), Xylopia aethiopica (33.7 g/100 g), Fagara leprieuri (32.1 g/100 g), and Aframomum daniellii (23.1 g/100 g). All the plants were rich in phenols, carotenoids, vitamin E and C. They are dark in colour and in solution they tended to provoke a fair acidification.

关键词： Spices Proximate Composition Minerals Vitamins

Electrocatalytic hydrogen peroxide formation on mesoporous non-metal nitrogen-doped carbon catalyst

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Journal of Energy Chemistry 2016年第2期25卷 249-255页

作者： Frédéric Hasché Mehtap Oezaslan Peter Strasser Tim-Patrick Fellinger Technische Universitat Berlin Department of Chemistry10623 BerlinGermany Max Planck Institut fur Kolloid-und Grenzfliichenforschung Department of Colloids14424 PoadamGermany carl von Ossietzky University of Oldenburg Department of ChemistryElectrocatalysis26111 OldenburgGermany

direct electrochemical formation of hydrogen peroxide（H2O2） from pure O2 and H2on cheap metal-free earth abundant catalysts has emerged as the highest atom-efficient and environmentally friendly reaction pathway and is therefore of great interest from an academic and industrial point of view. Very recently,novel metal-free mesoporous nitrogen-doped carbon catalysts have attracted large attention due to the unique reactivity and selectivity for the electrochemical hydrogen peroxide formation [1–3]. In this work,we provide deeper insights into the electrocatalytic activity, selectivity and durability of novel metal-free mesoporous nitrogen-doped carbon catalyst for the peroxide formation with a particular emphasis on the influence of experimental reaction parameters such as p H value and electrode potential for three different electrolytes. We used two independent approaches for the investigation of electrochemical hydrogen peroxide formation, namely rotating ring-disk electrode（RRdE） technique and photometric UV–VIS technique. Our electrochemical and photometric results clearly revealed a considerable peroxide formation activity as well as high catalyst durability for the metal-free nitrogen-doped carbon catalyst material in both acidic as well as neutral medium at the same electrode potential under ambient temperature and pressure. In addition, the obtained electrochemical reactivity and selectivity indicate that the mechanisms for the electrochemical formation and decomposition of peroxide are strongly dependent on the p H value and electrode potential.

关键词： Electrochemical hydrogen peroxide formation Selectivity Mesoporous nitrogen-doped carbon Green synthesis Electrocatalysis Metal-free catalysis

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Coexpression of receptor-tyrosine-kinases in gastric adenocarcinoma-a rationale for a molecular targeting strategy?

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World Journal of Gastroenterology 2007年第26期13卷 3605-3609页

作者： daniel drescher Markus Moehler Ines Gockel Kirsten Frerichs Annett Müller Friedrich dünschede Thomas Borschitz Stefan Biesterfeld Martin Holtmann Thomas Wehler Andreas Teufel Kerstin Herzer Thomas Fischer Martin R Berger Theodor Junginger Peter R Galle carl C Schimanski department of General and Abdominal Surgery Johannes Gutenberg University of Mainz MainzGermany First department of Internal Medicine Johannes Gutenberg University of Mainz MainzGermany Institute of Pathology Johannes Gutenberg University of MainzMainzGermany Third department of Internal Medicine Johannes Gutenberg University of Mainz MainzGermany Unit of toxicology and chemotherapy German Cancer Research CenterGermany

AIM: To define the (co-)expression pattern of target receptor-tyrosine-kinases (RTK) in human gastric adenocarcinoma. METHOdS: The (co-)expression pattern of VEGFR1-3,PdGFRα/b and EGFR1 was analyzed by RT-PCR in 51 human gastric adenocarcinomas. In addition,IHC staining was applied for confirmation of expression and analysis of RTK localisation. RESULTS: The majority of samples revealed a VEGFR1 (98%),VEGFR2 (80%),VEGFR3 (67%),PdGFRα (82%) and PdGFRβ(82%) expression,whereas only 62% exhibited an EGFR1 expression. 78% of cancers expressed at least four out of six RTKs. While VEGFR1-3 and PdGFRα revealed a predominantly cytoplasmatic staining in tumor cells,accompanied by an additional nuclear staining for VEGFR3 ,EGFR1 was almost exclusively detected on the membrane of tumor cells. PdGFRβ was restricted to stromal pericytes,which also depicted a PdGFRα ***-tyrosine-kinases coexpression in gastric adenocarcinoma and might therefore encourage an application of multiple-target RTK-inhibitors within a combination therapy.

关键词：胃癌病理组织治疗临床

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武汉市私立学校中学生吸烟状况的初步分析

中国学校卫生 2003年第3期24卷 214-215页

作者：张德新柳春红陈心广龚洁李燕 carl Andyson Johnson 湖北省武汉市疾病预防控制中心 430022 美国南加州大学

目的　了解私立学校中学生的吸烟状况 ,为加强青少年吸烟行为的干预措施提供依据。方法　以美国南加州大学提供的“青少年控烟项目调查问卷”为基础 ,对武汉市 8所私立学校 1 30 7名中学生进行问卷调查。以尝试吸烟率、吸过一整支烟的... 详细信息

目的　了解私立学校中学生的吸烟状况 ,为加强青少年吸烟行为的干预措施提供依据。方法　以美国南加州大学提供的“青少年控烟项目调查问卷”为基础 ,对武汉市 8所私立学校 1 30 7名中学生进行问卷调查。以尝试吸烟率、吸过一整支烟的吸烟率、过去 30d吸烟率、吸过 1 0 0支烟吸烟率描述学生的吸烟行为。结果　中学生的初始吸烟年龄平均为 1 1 .2岁 ;尝试吸烟率为 54 .0 % ,吸过 1整支烟的比例为 2 2 .0 % ,过去 30d内吸烟率为 1 9.4 % ,吸烟 >1 0 0支的学生占 4 .4 % ;吸烟情况分析中 ,54 .1 %的学生是在好奇的情况下抽烟 ;吸烟来源中 ,46 .0 %的学生报告香烟是从朋友或同学那里得到的。结论　私立学校中学生的吸烟状况严重。

关键词：中小学生卫生保健服务吸烟学校,私立

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运动和疾病中的肠液体吸收

体育科学 2001年第2期21卷 89-91页

作者：兰光史小才 carl Gisoifi Ronald Maughan Lawrence Schiller Leo Heitlinger J. Mare Rhoads Raul A. Wapnir Ph. d.department of Exercise Science University of Iowa Ph. d. department of Environment/Occupational Medicine University of Aberdeen M. d.department of Internal MedicineBaylor University Waco M. d.department of Pediatrics Ohio State University Columbus M. d.department of Pediatrics University of North Carolina Chapel Hill Ph. d.department of Pediatrics Cornell University Medical Collge

20世纪50年代以来，人们发现肠里葡萄糖的存在促进钠的转运（Riklis & Quastrel,1958）,这个里程碑式的发现引发口服补水溶液配方的产生。为满足水、耕作碳水化合物和电解质最大限度的吸收，精确配制这些溶液的问题激起了相当多的科学... 详细信息

20世纪50年代以来，人们发现肠里葡萄糖的存在促进钠的转运（Riklis & Quastrel,1958）,这个里程碑式的发现引发口服补水溶液配方的产生。为满足水、耕作碳水化合物和电解质最大限度的吸收，精确配制这些溶液的问题激起了相当多的科学研究和讨论。

关键词：运动疾病肠液体吸收口服补水溶液渗透压吸收能力纳碳水化合物

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detection and Characterization of β-Lactamase Encoding Genes in Carbapenem Non-Susceptible Gram-Negative Bacteria and Susceptibility of Isolates to Ceftazidime-Avibactam at a New York City Community Hospital

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Open Journal of Medical Microbiology 2016年第4期6卷 150-157页

作者： carl Urban Rita Colon-Urban Vincent J. LaBombardi Noriel Mariano Nishant Prasad Geeti dhillon Marina Guralnik Sorana Segal-Maurer The dr. James J. Rahal Jr. Division of Infectious Diseases Department of Medicine New York-Presbyterian/Queens Flushing NY USA The dr. James J. Rahal Jr. Division of Infectious Diseases Department of Medicine NewYork-Presbyterian/Queens Flushing NY USA department of Biological Sciences SUNY Old Westbury Old Westbury New York NY USA department of Pathology NewYork-Presbyterian/Queens Flushing NY USA

A surveillance study was undertaken to identify prominent β-lactamase encoding genes in 131 carbapenem non-susceptible gram-negative clinical isolates at a New York City community hospital. KPC carbapenemases were detected in 89% of Enterobacteriaceae as well as additional TEM, SHV, and CTX-M class A enzymes. OXA-23 and OXA-24 were the prevalent class d carbapenemases identified in Acinetobacter species. One OXA-23 in M. morganii and one OXA-48 in K. pneumoniae were also identified. Among class C β-lactamases CMY, ACT/MIR, dHA, and FOX were detected. The in vitro activity of ceftazidime-avibactam by E-test methodology was tested with minimal inhibitory concentrations (MIC) of ≤3 μg/ml for 97.8% of all Enterobacteriaceae, MIC50/90 of 16/>256 μg/ml for carbapenem non-susceptible Acinetobacter, and 3/6 μg/ml for carbapenem non-susceptible Pseudomonas aeruginosa. Periodic surveillance of isolates to characterize current and emerging β-lactamase genotypes present in local isolates may help identify outbreak situations, provide assistance to infection control and antibiotic stewardship programs, and potentially improve patient outcomes.

关键词： Carbapenem Non-Susceptible Check-MdR CT103 XL Microarray β-Lactamase detection Resistance Mechanisms Ceftazidime-Avibactam

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评定洁净室用手套的耗散特性

洁净与空调技术 2001年第1期 46-47+49-50+56页

作者： Andrew J.Magenheim,carl Newburg Ph.d

两个物体相接触时总会产生一定数量的电荷。减少静电放电(ESd)损害的主要机理是把电荷导入地下。可以用两种测量方法来评定一种材料或一种产品耗散电荷的能力;电荷衰减时间和电阻。如果电阻是已知的,就可预知沿相同路径的衰减时间。这... 详细信息

两个物体相接触时总会产生一定数量的电荷。减少静电放电(ESd)损害的主要机理是把电荷导入地下。可以用两种测量方法来评定一种材料或一种产品耗散电荷的能力;电荷衰减时间和电阻。如果电阻是已知的,就可预知沿相同路径的衰减时间。这里只提到了电阻—对洁净室用手套的测量结果,并对电阻及手套材料之间的相关性进行了探讨。

关键词：手套操作员洁净室净化室电阻测量集中参数测量电荷测量结果

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中学生膳食营养摄入与自我体重意识研究

现代预防医学 2008年第10期35卷 1842-1846页

作者：柳春红 carl Andersn Johson Chih-ping Chou Paula Healani Palmer 孙秀发华南农业大学食品学院美国南加利福尼亚大学华中科技大学同济医学院

[目的]研究中学生自我体重意识对膳食营养摄入的影响。[方法]以24h膳食回顾方法收集学生2d的膳食资料,同时以问卷收集学生自我体重意识相关信息。[结果]男生大部分营养素摄入显著高于女生;感觉偏胖的学生其能量、总脂肪、碳水化合物、... 详细信息

[目的]研究中学生自我体重意识对膳食营养摄入的影响。[方法]以24h膳食回顾方法收集学生2d的膳食资料,同时以问卷收集学生自我体重意识相关信息。[结果]男生大部分营养素摄入显著高于女生;感觉偏胖的学生其能量、总脂肪、碳水化合物、维生素B1、烟酸、铁、锌的摄入量明显低于感觉偏瘦和感觉适中的学生;当学生对自身体重的满意程度依次从不满意、一般、到满意时,碳水化合物、膳食纤维、铁摄入量依次显著增高;打算减轻体重的学生其能量、蛋白质、总脂肪、碳水化合物、维生素B1、铁、锌均显著低于其他各组。[结论]应加强对中学生营养状况、体重的监测,并引导学生正确看待体重问题,避免盲目的体重控制和饮食限制。

关键词：中学生膳食营养营养素自我体重意识