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In situ observation of synthesized nanoparticles in ultra-dilute aerosols via X-ray scattering

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Nano Research 2019年第1期12卷 25-31页

作者： Sarah R.McKibbin Sofie Yngman Olivier Balmes Bengt O.Meuller Simon Tagerud Maria E.Messing Giuseppe Portale Michael Sztucki Knut Deppert Lars Samuelson Martin H.Magnusson Edvin lundgren Anders Mikkelsen Department of Physics and Nanolund Lund UniversityBox 11822100 LundSweden MaxIV Laboratory Lund UniversityBox 11822100 LundSweden University of Groningen Zemike Institute for Advanced MaterialsNijenborgh 4NL-9747 AG GroningenThe Netherlands ESRF-The European Synchrotron CS 4022038043 Grenoble Cedex 9France

In-air epitaxy of nanostructures(Aerotaxy)has recently emerged as a viable route for fast,large-scale *** this study,we use small-a ngle X-ray scatteri ng to perform direct in-flight characterizati ons of the first step of this process,i.e.,the en gineered formatio n of Au and Pt aerosol nan oparticles by spark gen erati on in a flow of N2 *** represe nts a particular challe nge for characterizati on because the particle density can be extremely low in con trolled *** particles produced are exami ned duri ng producti on at operatio nal pressures close to atmospheric conditions and exhibit a log no rmal size distributi on ranging from *** Au and Pt particle productio n and detection are *** observe and characterize the nanoparticles at different stages of synthesis and extract the corresponding domi nant physical properties,in cludi ng the average particle diameter and sphericity,as in flue need by particle sintering and the prese nee of *** observe highly sorted and sin tered spherical Au nano particles at ultra-dilute concen tratio ns(<5×10^5 particles/cm^3)corresponding to a volume fraction below 3×10^-10,which is orders of magnitude below that of previously measured *** independently confirm an average particle radius of 25 nm via Guinier and Kratky plot *** study indicates that with high-intensity synchrotron beams and careful con sideratio n of backgro und removal,size and shape info rmati on can be obtai ned for extremely low particle concentrations with industrially relevant narrow size distributions.

关键词： aerosol nanoparticle synthesis in situ analysis small-angle X-ray scattering Aerotaxy

Trichome-Specific Expression of Amorpha-4,11-Diene Synthase, a Key Enzyme of Artemisinin Biosynthesis in <i>Artemisia annua</i>L., as Reported by a Promoter-GUS Fusion

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American Journal of Plant Sciences 2011年第4期2卷 619-628页

作者： Hongzhen Wang Linda Olofsson Anneli lundgren Peter E. Brodelius 不详

Artemisia annua L. produces small amounts of the sesquiterpenoid artemisinin, which is used for treatment of malaria. A worldwide shortage of the drug has led to intense research to increase the yield of artemisinin in the plant. In order to study the regulation of expression of a key enzyme of artemisinin biosynthesis, the promoter region of the key enzyme amorpha-4,11-diene synthase (ADS) was cloned and fused with the β-glucuronidase (GUS) reporter gene. Transgenic plants of A. annua expressing this fusion were generated and studied. Transgenic plants expressing the GUS gene were used to establish the activity of the cloned promoter by a GUS activity staining procedure. GUS under the control of the ADS promoter showed specific expression in glandular trichomes. The activity of the ADS promoter varies temporally and in old tissues essentially no GUS staining could be observed. The expression pattern of GUS and ADS in aerial parts of the transgenic plant was essentially the same indicating that the cis-elements controlling glandular trichome specific expression are included in the cloned promoter. However, some cis-element(s) that control expression in root and old leaf appears to be missing in the cloned promoter. Furthermore, qPCR was used to compare the activity of the wild-type ADS promoter with that of the cloned ADS promoter. The latter promoter showed a considerably lower activity than the wild-type promoter as judged from the levels of GUS and ADS transcripts, respectively, which may be due to the removal of an enhancing cis-element from the ADS promoter. The ADS gene is specifically expressed in stalk and secretory cells of glandular trichomes of A. annua.

关键词： Agrobacterium Tumefaciens Amorpha-4 11-Diene Synthase Artemisia annua Artemisinin Biosynthesis β-Glucuronidase Gene Regulation Promoter Activity Stable Transformation

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低效的C++ 真是这样吗?

中国电子商情(基础电子) 2008年第8期 61-64页

作者： Anders lundgren IAR Systems

C++可以为嵌入式编程人员提供一些优于C语言的显著特点。在刚开始,C++可以简单的作为一个更好的C使用:正如一些C编程者用C++编译器运行代码进行质量检验。这也表明,转向使用C++所带来的利弊并不是绝对的:正如本文所述,你可以选择一些对... 详细信息

C++可以为嵌入式编程人员提供一些优于C语言的显著特点。在刚开始,C++可以简单的作为一个更好的C使用:正如一些C编程者用C++编译器运行代码进行质量检验。这也表明,转向使用C++所带来的利弊并不是绝对的:正如本文所述,你可以选择一些对应用有用的C++功能,而不要其他功能。相比于C,C++更加强大的类型检验可以在编译时发现更多的错误,实现精确的内存控制和开发出更紧凑的执行代码。改用面向对象的方法可以提供更好的调试和维护代码的功能

关键词：代码维护对象指针编译器编译程序构造函数名字空间操作符重载迭代器函数调用虚函数成员函数

Global Locate LTO技术的过去、现在与未来——GPS辅助数据技术

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电子与电脑 2006年第9期6卷 90-96页

作者： David lundgren Frank van Diggelen Global Locate

本文介绍Global Locate的长期轨道（Long Term Orbit ,LTO）技术，有时又称为“扩充式星历表”（extended ephemeris）技术，LTO是一种GPS辅助数据，不需无线连接到辅助性全球定位系统（Assisted GPS,A-GPS）服务器就能提供辅助数据给A-... 详细信息

本文介绍Global Locate的长期轨道（Long Term Orbit ,LTO）技术，有时又称为“扩充式星历表”（extended ephemeris）技术，LTO是一种GPS辅助数据，不需无线连接到辅助性全球定位系统（Assisted GPS,A-GPS）服务器就能提供辅助数据给A-GPS装置。传统A-GPS系统虽然大幅改善GPS效能，但是A-GPS装置几乎每小时都要连接到A-GPS服务器以便下载最新的辅助数据。LTO数据则可透过因特网获得，而且有效期限长达数天，这使得连接需求大幅降低。

关键词： A-GPS LTO技术数据技术辅助数据全球定位系统无线连接 Orbit

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有肺气肿的大鼠吸入239PuO2后在肺中的沉积、分布与滞留

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国际放射医学核医学杂志 1982年第3期 181-182页

作者： lundgren DL ,孙金锴

慢性阻塞性肺疾患与吸烟或吸入各种污染物有关。慢性阻塞性肺疾患如肺气肿对吸入污染物更为敏感。动物吸入核素的剂量-效应研究有助于对人吸入核素的生物效应的估计,有肺疾患存在的机体将改变核素在肺中的沉积、分布和滞留,从而改变辐... 详细信息

慢性阻塞性肺疾患与吸烟或吸入各种污染物有关。慢性阻塞性肺疾患如肺气肿对吸入污染物更为敏感。动物吸入核素的剂量-效应研究有助于对人吸入核素的生物效应的估计,有肺疾患存在的机体将改变核素在肺中的沉积、分布和滞留,从而改变辐射剂量与生物效应。肺气肿的模型可用气管内注入弹性硬蛋

关键词：肺气肿气管内肺疾病 PuO2 大鼠

费用价:对林木生长各种方案进行经济评价的一项有用标准

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林草资源研究 1983年第2期 63-69页

作者： A.L.lundgren ,枞栎

绪言对于一项投资有几种看法: 1.收入是否会大于成本? 2.所投资金按什么速率增长? 3.每投入1元能得回什么? 4.所投资金需多长时间才能回收? 5.生产一单位产品的成本如何?

关键词：轮伐期立地条件立地指数商品材贴现成本立方英尺班克松板英尺木材产品林木生长经济

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先进的铁道车辆检查系统

国外铁道车辆 2007年第1期44卷 40-46页

作者： Jim lundgren[美] 张蓉（编译）阎锋（校）

先进的铁道车辆检查系统能提高铁路的安全性、降低成本并改善客户服务。本文重点介绍了闸瓦和车轮轮廓检查系统的试验、现场考验和运用情况。

关键词：铁道车辆检查系统试验

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Effects of estrogen and testosterone therapy on serum metabolites in postmenopausal women

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Effects of estrogen and testosterone therapy on serum metabo...

扩散式气溶胶粒子大小测定仪中不同筛网的透过率

2011中国妇产科学术会议暨浙江省计划生育与生殖医学学术年会暨生殖健康讲习班

作者： Moritz Thomas lundgren Krister Norstedt Gunnar Hirschberg Angelica L Tollet-Egnell Petra Department of Obstetrics and Gynecology The First Affiliated HospitalDalian Medical University Department of Obstetrics and Gynecology Karolinska University HospitalStockholmSweden Umea Plant Science Center Department of Forest Genetics and Plant PhysiologySwedish University of Agricultural SciencesUmeaSweden The Department of Molecular Medicine and Surgery Karolinska InstitutetStockholmSweden

Objective To study effects of estrogen and testosterone therapy on serum metabolites in postmenopausal women,and explore possible relationships between the serum metabolites and carbohydrate/lipid metabolism. Methods Sixty naturally postmenopausal women were randomly assigned to treatment with testosterone undecanoate 40 mg every second day(T group);estradiol valerate 2 mg daily(E group);or the combination of both(T+E group). Serum metabolites were determined by gas chromatography-mass spectrometry/time-of-fight(GC/TOF-MS) before and

关键词： metabolites hormone therapy insulin sensitivity lipid metabolism postmenopausal women

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卫生研究 1986年第1期 35-39页

作者：徐立大,D.A.lundgren 中国预防医学中心卫生研究所卫生防护研究室美国佛罗里达大学

试验了不同粒径亚微米气溶胶通过200目、400目、500目及635目不锈钢筛网的透过率。发现实验结果与Cheng的公式相吻合。除635目外,与Rangaraj公式计算的结果有显著差异。对不同筛网分别归纳出较简单的实用公式,可作为仪器设计和编制测定... 详细信息

试验了不同粒径亚微米气溶胶通过200目、400目、500目及635目不锈钢筛网的透过率。发现实验结果与Cheng的公式相吻合。除635目外,与Rangaraj公式计算的结果有显著差异。对不同筛网分别归纳出较简单的实用公式,可作为仪器设计和编制测定结果计算程序的基础。

关键词：筛网目数层数透过率透过系数扩散式气溶胶粒子测定仪