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钨卡宾化合物与水的不寻常反应——含氧配体三聚体的合成、表征和晶体结构(英文)

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中国科学：化学 2012年第1期42卷 93-94页

作者： dougan brenda a 薛子陵美国田纳西大学化学系

烷基卡宾化合物W(CH2CMe3)3(/CSiMe3)(1)与水在四氢呋喃(THF)中,或者与重水在苯-d6中的反应分别生成两个新的含氧配体的三聚物W3O3(μ=O)3(CH2CMe3)6(THF)3(2)和[W3O3(μ=O)3(CH2CMe3)6(D2-O)3]·2benzene-d6(3·2benzene-d6).这两个产物中每个钨原子均含两个烷基配体,与以前报道过的从类似的烷基卡宾化合物W(CH2CMe3)3(/CCMe3)与水反应所生成的二聚物W2O2(μ-O)(CH2CMe3)6有很大不同.化合物1与重水在四氢呋喃的反应中,观测到一个不稳定的中间体W2O2(μ-O)(CD2SiMe3)2(CH2CMe3)4(4-d4).对1与水或者与重水在THF-d8中的反应生成4及4-d4进行了动力学研究,在298(1)K,动力学同位素效应(KIE)为3.46(3),显示1的消失是一个速率决定步骤.

关键词：烷基卡宾化合物水含氧配合物动力学同位素效应

Polarized neutron diffraction and its application to spin density studies

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Science China Chemistry 2009年第12期52卷 2083-2095页

作者： brenda A. dougan Department of Chemistry The University of Tennessee

Spin density distributions in molecular compounds containing unpaired electrons have been studied by polarized neutron diffraction (PND). The spin density distributions provide a unique perspective of the magnetic properties of the compounds. The background and fundamentals of polarized neutron diffraction are summarized in this review,followed by examples of applications in inorganic and organic chemistry. Spin densities in several compounds that are obtained by polarized neutron diffraction are highlighted. Spin densities in single molecular magnet [Fe8O2(OH)12(tacn)6]8+ and cyano-bridged K2[Mn(H2O)2]3[Mo(CN)7]2·6H2O demonstrate how to obtain magnetic interaction in the complexes by PND. PND studies of Ru(acac)3,containing one single unpaired electron,show small spin densities in this complex. Finally the use of PND in studying nitronyl nitroxide radicals is given. Our goal in this review is to illustrate how PND functions and how it serves as a sensitive tool in directly probing spin density in molecules.

关键词： polarized neutron diffraction spin (unpaired electron) density paramagnetic antiferromagnetic magnetic structure factor

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极化中子衍射及在电子自旋密度研究中的应用

中国科学（B辑） 2009年第12期39卷 1569-1582页

作者： brenda A. dougan 薛子陵 Department of Chemistry The University of TennesseeKnoxville Tennessee 37996-1600 USA

极化中子衍射方法常用于研究含未配对电子化合物中电子自旋密度的分布.分子中电子自旋密度分布从一个独特的角度反映化合物的磁性质.本文介绍极化中子衍射方法的背景知识和基本原理.包括中子源、中子和X射线衍射、极化中子衍射,以及一... 详细信息

极化中子衍射方法常用于研究含未配对电子化合物中电子自旋密度的分布.分子中电子自旋密度分布从一个独特的角度反映化合物的磁性质.本文介绍极化中子衍射方法的背景知识和基本原理.包括中子源、中子和X射线衍射、极化中子衍射,以及一些常用的实验数据处理方法.选用几个实例总结了用极化中子衍射方法得到的电子自旋密度分布在无机和有机化学中的应用.通过单分子磁体[Fe8O2(OH)12(tacn)6]8+和氰基桥联化合物K2[Mn(H2O)2]3[Mo(CN)7]2·6H2O,说明如何用该方法研究金属原子间的磁相互作用;并通过Ru(acac)3这个只含一个未配对电子的化合物来说明如何获得化合物中金属和配体上小的自旋密度;最后介绍了该方法在nitronyl nitroxide自由基研究中的应用.

关键词：极化中子衍射电子自旋(或未配对电子)密度顺磁反铁磁磁结构因子

Investigation of operational parameters for an industrial CFB combustor of coal,biomass and sludge

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China Particuology 2007年第4期5卷 247-254页

作者： Manon Van de Velden Jan Baeyens Bill dougan Alan McMurdo Department of Chemical Engineering University of Birmingham B15 2TT Birmingham United Kingdom UPM-Kymmene Caledonian Paper Ltd.AyrUnited Kingdom

The combustion of coal and/or biomass （sludge, wood waste, RDF, etc.） in a circulating fluidized bed has been a commercial topper for over 20 years, and references to principles and applications are numerous and widespread although few data are presented concerning the operation of large scale CFB-units. The authors studied the CFB-combustion at UPM-Kymmene （Ayr）, a major paper mill relying for its steam production upon the combustion of coal （80-85 %）, wood bark （5-10%） and wastewater treatment sludge （5-10%）. The maximum capacity of the CFB is 58 MWth. A complete diagnostic of the operation was made, and additional tests were performed to assess the operating mode. The plant schematics, relevant dimensions and process data are given. To assess the operation of the UPM-CFB, it is important to review essential design parameters and principles of CFB combustors, which will be discussed in detail to include required data, heat balance and flowrates, operating versus transport velocity, kinetics and conversion （including the possible effect of the Bouduard reaction if carbon is present）. Since the residence time in the riser and the cyclone efficiency determine the burnout of circulating fuel-particles, the UPM-CFB was subjected to a stimulus response technique using nickel oxide as tracer. Results illustrate the efficiency of the cyclone separation and the number of recycle loops for particles of a given size. Results will also be used to assess the cyclone operation and efficiency and to comment upon expected and measured carbon conversion.

关键词： Circulating fluidized bed Combustion Coal Biomass Operation Cyclone

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金属卡拜与双卡宾的转换和α-夺氢反应

金属卡拜与双卡宾的转换和α-夺氢反应

Novel Automated Paced Fractionation Detection Algorithm for Ablating Ventricular Tachycardia

中国化学会第26届学术年会无机与配位化学分会场

作者： brenda A.dougan 薛子陵美国田纳西大学化学系美国田纳西大学化学系

＜正＞金属卡宾和卡拜化合物被广泛地应用烯烃和炔烃催化复分解反应。我们曾报道了卡拜-烷基膦配合物与双卡宾-烷基膦配合物进行α-氢转移反应并达到平衡。我们最近研究了（Me3SiCH2）3W（≡CSiMe3）

关键词：卡宾卡拜烷基膦

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Journal of Biomedical Science and Engineering 2016年第10期9卷 488-500页

作者： Divyanshu Gupta Mohammad Hassan Shariat Madelaine Baetz-dougan Javad Hashemi Selim Akl Damian Redfearn Queen’s University Kingston Canada Kingston General Hospital Kingston Canada

Catheter ablation therapy has become a key intervention in treatment of ventriculartachycardia (VT). However, current fractionation mapping methods used to isolate the ablation targets in VT patients are done manually, and are therefore time consuming. They also have limited success rates (50% recurrence rate within 2 years). We present a fully automated fractionation detection algorithm for patients with VT which expands on previously defined fractionation features and which substantially decreases associated study times. Paced electrogram signals were collected from six patients during electrophysiologic study according to a modified paced electrogram fractionation analysis protocol. Data were exported and analyzed offline using custom written software. Electrograms from right ventricular pacing catheter were used as reference. Surface electrograms, along with ventricular geometry and relative catheter locations, were used to identify physiological interference and physiologically irrelevant features. A total of 264 electrograms, collected from a roving catheter, were manually and automatically annotated for fractionation as defined by three features: conduction time (CT), electrogram duration (ED), and number of deflections (ND). Of these, 60 were selected manually to have no discernable features and were successfully discarded by our algorithm;yielding a specificity of 100%. Of the remaining 204, 16 were erroneously discarded by our algorithm;yielding a sensitivity of 92.16%. A comparison between annotations showed correlations of 0.98, 0.97, and 0.94 for AL, ED, and ND respectively.

关键词： Teagers-Kaiser Energy Operator Ischemia Ventricular Mapping

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蚂蚁结“奇缘”

疯狂英语(新策略) 2014年第7期 15-18页

作者： Terrell dougan 铖铖

像橡树般一寸寸成长起来的友情,要比像瓜蔓般突然蹿起来的友情更为可靠。——夏洛蒂·勃朗特(Charlotte Bront(e|¨))我们在彼此后院间一块地里的蚁丘上相遇。我从后门走出来,看到个子如我一般大的一个小女孩站在那儿,看着蚂蚁们忙活着... 详细信息

像橡树般一寸寸成长起来的友情,要比像瓜蔓般突然蹿起来的友情更为可靠。——夏洛蒂·勃朗特(Charlotte Bront(e|¨))我们在彼此后院间一块地里的蚁丘上相遇。我从后门走出来,看到个子如我一般大的一个小女孩站在那儿,看着蚂蚁们忙活着。突然,她一脚跺在一群勤劳的蚂蚁上,而这些蚂蚁只不过是在忙着自己的活儿而已。这让我气愤不已。我双手往她肩上使劲儿一推,她摔倒了。

关键词：埃莉诺修道院摩门教徒

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分子生物学、新遗传学与疫苗进展

世界科学 1989年第3期 31-34页

作者： G.dougan 郝军山

在分子生物学和新遗传学方面的进展正为发展更安全、更有效的疫苗开辟新途径。我们业已在分子水平上对宿主如何做到免疫、防犯,以及如何同侵入的病原体相互作用所有了解。现在正在对重要的保护性成分加以鉴定,对减毒烈性病原体的新方法... 详细信息

在分子生物学和新遗传学方面的进展正为发展更安全、更有效的疫苗开辟新途径。我们业已在分子水平上对宿主如何做到免疫、防犯,以及如何同侵入的病原体相互作用所有了解。现在正在对重要的保护性成分加以鉴定,对减毒烈性病原体的新方法尚在应用之中。对抗原呈现的变换途径也在开发之中。唯一的目标也许是发展全合成疫苗。本文拟对该领域的研究进展及其意义进行讨论。

关键词：疫苗减毒原生动物菌苗抗原百日咳博德特氏菌宿主分子生物学遗传学

The New Immigrant Ethic

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ChinAfrica 2011年第3期3卷 56-56页

作者： Kwame dougan

AMY Chua’s parenting is grounded in a fear of failure,but her authoritarian style is no more exclusively Chinese than rice is:it can be found operating, to varying degrees of rigor,in most homes of recently arrived - and relatively poor - immigrants. I call this take-no-prisoners type of parenting the "new immigrant ethic." And as a black African immigrant to the West,I overcame significant odds,odds that don’t factor in Chua’s life and her Chinese-mother parenting model.

关键词： The New Immigrant Ethic