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保德河盆地莫里页岩的固态核磁共振特征

地质地球化学 1995年第3期23卷 29-33页

作者： f.P.Miknis 吴元江苏油田地科院

对怀俄明州保德河盆地莫里页岩的一组生油岩样品进行了固态13C核磁共振（NMR）测量。这项研究的目的是几CP／MAS13CNMR测量来监测由埋深引起的干酪根碳结构的变化。NMR测量样品的现今埋深为3000～11500英尺1）。由于总有机碳含量主要为... 详细信息

对怀俄明州保德河盆地莫里页岩的一组生油岩样品进行了固态13C核磁共振（NMR）测量。这项研究的目的是几CP／MAS13CNMR测量来监测由埋深引起的干酪根碳结构的变化。NMR测量样品的现今埋深为3000～11500英尺1）。由于总有机碳含量主要为（1～2）Wt％，在13CNMR测量中使用了大容量的样品旋转器。用HCI清洗样品能提高13C谱图的质量。干酪根的芳香度随理深的增加而增加，在深度超过10000英尺时，由于干酪根中残留的脂肪族碳很少，几乎不能再生油。结合NMR和生油岩评价数据，得到了氢聚散的估算结果。计算表明，约有20％的干酪根转化为烃类，由于芳构化和缩合反应，释放出足够的氢，而使产物稳定下来。

关键词：页岩岩样固态核磁共振

THE EffECT Of MINE TAILINGS ON LEVELS Of HEAVY METALS IN SEAWATER

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Acta Oceanologica Sinica 1986年第3期5卷 401-415页

作者： C.S.WONG,f.A.WHITNEY,W.K.JOHNSON,LU XIANKUN,WUJINPING,WUSHENGSAN,LIJINXIA Ocean Chemistry Division Institute of Ocean Sciences Sidney B.C. Canada Ocean Chemistry Division Institute of Ocean Sciences Sidney B.C. Canada Ocean Chemistry Division Institute of Ocean Sciences Sidney B.C. Canada Shandong College of Oceanology Qingdao China Third Institute of Oceanography State Oceanic Administration Xiamen China Third Institute of Oceanography State Oceanic Administration Xiamen China Third Institute of Oceanography State Oceanic Administration Xiamen China

Changes in levels of heavy metals in seawater resulting from the addition of mine tailings were studied using plastic enclosures. Nominal concentrations of 10 mg l-1 and 100 mg l-1 of mine tailings from a B. C. molybdenum mine were added, and the metal levels were followed together with sedimentation rates, particle size distribution and other oceanographic and biological time-series parameters over sixteen days. No substantial elevation in levels of zinc, cadmium and copper was observed in the tailing bags compared to that in a background control bag with no addition of tailings. Lead showed a substantial increase in seawater following tailing addition and its removal apparently was with detritus settling following a plankton bloom, and inorganic settling of fine tailing particles.

关键词： Pb THE EffECT Of MINE TAILINGS ON LEVELS Of HEAVY METALS IN SEAWATER Cd

Mine tailings storage dams modify upstream headwater fish assemblages

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Water Biology and Security 2023年第2期2卷 32-42页

作者： Gilberto N.Salvador Robert M.Hughes fabio Vieira Raphael Ligeiro Luciano f.A.Montag Ecology and Conservation Laboratory(LABECO) Federal University of ParaBiological Sciences InstituteRua Augusto Correa01GuamaCaixaBelemPA479Brazil fish Ecology and Conservation Laboratory(Eco-Peixes) Federal University of Minas GeraisBiological Sciences InstituteAv.Antonio Carlos6627Belo HorizonteMGCEP:31.270-901Brazil Amnis Opes Institute 2895 SE GlennCorvallisOR97333USA Department of fisheries Wildlife&Conservation SciencesOregon State UniversityCorvallisOR97331USA Zoology Department Federal University of Minas GeraisBiological Sciences InstituteAv.Antonio Carlos6627CEP:31.270-901Belo HorizonteMGBrazil

Riverscape connectivity is a critically important component determining the ecological condition of lotic *** evaluated changes in fish assemblages caused by the loss of connectivity by mine tailings storage dams(TSDs),hypothesizing that headwater fish assemblages are restructured by TSDs located downstream,even though the upstream habitats are not *** used standard methods to collect fish in 24 first to third order sites,with half draining to TSDs(dammed)and the other half free from this impact(undammed).To identify differences between treatments,we used PERMANOVA to test both environmental variables and ichthyofauna composition(Bray-Curtis similarity index)and evaluated the biological metrics that most influenced assemblage composition *** expected,we observed no difference between treatments for environmental variables,but we did observe differences in fish assemblage *** also observed five metrics with lower values in dammed streams(richness and abundance of intolerant species,siluriform richness,and abundance of Pareiorhaphis *** and Trichomycterus brasiliensis)and two metrics with higher values in dammed streams(perciform richness and abundance of Oligosarcus argenteus).We believe these changes resulted from of stream fragmentation by TSDs,in addition to source-sink mechanisms and conclude that mine TSDs located downstream change headwater fish assemblages,an impact often neglected in biomonitoring and bioassessment studies.

关键词： Habitat fragmentation Source-sink dynamics Iron ore mining Rio Doce basin

Nanocomposite Materials for Cathodes and Electrolytes in Lithium Batteries

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复旦学报（自然科学版） 2005年第5期44卷 662-663页

作者： f. Croce C.R. Martin B.Scrosati L. Settimi C.Sides Dipartimento di Scienze del farmaco Università ‘G.D'Annunzio' 66013 Chieti ItalyChemistry Department University of Florida Gainesville FL USADipartimento di Chimica Università ‘La Sapienza' 00185 Roma ItalyDipartimento di Chimica Università ‘La Sapienza' 00185 Roma ItalyChemistry Department University of Florida Gainesville FL USA

Lithium-ion batteries are today the power sources of choice far portable electronics, a multi-billion dollar market[1]. This outstanding success has spawned great international interest in applying this technology to more demanding systems, such as electric of hybrid vehicles[2]. However, to achieve full success in this area,new electrode materials, less expensive, more energetic and more compatible with the environment than the present ones, have to be identified. Accordingly, intense R&D are in progress to reach this goal and few variable alternatives to the original lithium-ion battery design, have been proposed. Particularly interesting is the olivine-structured LifePO4 cathode developed by Goodenough and co-workers[3], which offers several appealing features, such as high, flat voltage profile and relatively high specific capacity, combined with low cost and low toxicity. However, LifePO4 has one crucial disadvantage, i.e. its inherently low electric conductivity which reflects in the inability to deliver high capacity at high discharge rates. Such as poor rate capability has been the object of investigation by various groups who have proposed different approaches to overcome it, including carbon coating[4], nano-fibril textures[5], optimized synthesis procedures[6] and foreign metal doping[7].

关键词：纳米复合材料锂电池阴极电解液聚合体

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评斯旺尼克的《音乐、心智与教育》

世界社会科学 1991年第8期 79-81页

作者： M.f.麦卡锡 ,禾子

在《音乐、心智和教育》一书中,K.斯旺尼克为英国的音乐教育提出了一种理论。他继承了卡尔·波佩尔的传统,认为“人类和科学的中心活动不过是对各种理论的诋毁和赞誉”。他不仅阐述理论问题,而且亲自谱曲。在书中,他以5章篇幅从理论上... 详细信息

在《音乐、心智和教育》一书中,K.斯旺尼克为英国的音乐教育提出了一种理论。他继承了卡尔·波佩尔的传统,认为“人类和科学的中心活动不过是对各种理论的诋毁和赞誉”。他不仅阐述理论问题,而且亲自谱曲。在书中,他以5章篇幅从理论上探讨了音乐教育实践中的三个难题:音乐课程的结构、文化联系以及对学生水平进展的评价。本书的意义在于,他综合了过去20年来英国音乐教育研究的成果,分析了社会中的音乐与教育中的音乐之间的关系。

关键词：音乐英国世界观学校大不列颠及北爱尔兰联合王国学堂世界音乐教育尼克音乐教学音乐教育体系斯旺心智

Impact of gender and race on expectations and outcomes in total knee arthroplasty

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World Journal of Orthopedics 2020年第5期11卷 265-277页

作者： Brian A Perez James Slover Emmanuel Edusei Annamarie Horan Afshin Anoushiravani Atul f Kamath Charles L Nelson Department of Orthopedics University of PennsylvaniaPhiladelphiaPA 19104United States Department of Orthopedic Surgery New York University Langone HealthNew YorkNY 10016United States Department of Orthopaedic Surgery Cleveland ClinicClevelandOH 44195United States

BACKGROUND Total joint arthroplasty is one of the most common surgeries performed in the United States with total knee arthroplasty(TKA)being one of the most successful surgeries for restoring function and diminishing *** with the demonstrated success of TKA and a higher prevalence of arthritis and arthritis related disability among minorities,racial and gender disparity remains a constant issue in providing care for the adult reconstruction *** To assess the role of demographics and expectations on differences in perioperative patient reported outcomes(PRO)following *** One hundred and thirty-three patients scheduled for primary unilateral TKA secondary to moderate to severe osteoarthritis were enrolled in this twoinstitution prospective *** PRO questionnaires were collected at four time *** analysis was conducted to determine the impact of gender,ethnic background and expectation surveys responses to assess PRO at these time *** females were associated with worse preoperative Knee Injury and Osteoarthritis Outcome Scores(KOOS)for symptoms,pain,and activities of daily *** Americans were associated with worse KOOS for pain,activities of daily living,and quality of *** worse preoperative scores,no difference was noted in these categories between the groups ***,all pre-operative psychometric scales were equivalent across groups except Geriatric Depression scale,which was significantly different between groups within the Race and Age Group(Pficantly different for all subscales and total score within Age Group(Pfication,Helplessness subscales as well as the Total score were significantly different between groups for Race and Relationship Status(Pfemale and African American patients have lower preoperative KOOS scores compared to white male *** postoper

关键词： Knee Joints Arthroplasty Osteoarthritis Race Gender Postoperative Outcomes

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生态经济学——解决环境问题的新尝试

国外社会科学 1998年第3期 87-88页

作者：Ｆ．泽尔纳

生态经济学——解决环境问题的新尝试〔德〕Ｆ．泽尔纳鉴于物种灭绝、雨林破坏、臭氧洞和温室效应等全球性和长期性的环境问题，新古典环境经济学日益受到批评，人们提出了解决环境问题的新理论——生态经济学。１．新古典环境经济学新... 详细信息

生态经济学——解决环境问题的新尝试〔德〕Ｆ．泽尔纳鉴于物种灭绝、雨林破坏、臭氧洞和温室效应等全球性和长期性的环境问题，新古典环境经济学日益受到批评，人们提出了解决环境问题的新理论——生态经济学。１．新古典环境经济学新古典环境经济学特别把新古典经济学中...

关键词：生态经济学新尝试泽尔纳新古典经济学环境经济学

STUDY ON THE CONTROLLED MASS TRANSPORT THROUGH POROUS MEMBRANES

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化工学报 2000年第S1期51卷 15-19页

作者： Xu Xia and Cui Z. f (Department of Engineering Scinece, University of Oxford,OXI 3PJ, UK)

Cryopreservation of cells and tissues (natural or engineered) usually involves complicated protocols for addition and later removal of cryoprotecting agents to avoid osmotic shock and toxicity to cells. The rate of CPA addition and removal is essential to cell survival. In this study, the feasibility of using porous membrane to control the rate of CPA transfer to cell environment is studied, A purpose designed diffusion chamber was fabricated. The effects of membrane characteristics (porosity and effective thickness), temperature, and initial concentration were experimentally studied. A simplified mathematical model was developed, which provides the basis to desire the membrane parameters based on tile experimental measurements.

关键词： mass transport membranes diffusion rate control cryopreservation

Effect of reperfusion strategy on QT dispersion in patients with acute myocardial infarction:Impact on in-hospital arrhythmia

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World Journal of Cardiology 2023年第3期15卷 106-115页

作者： Mohamed Aboel-Kassem f Abdelmegid Mohamed M Bakr Hamdy Shams-Eddin Amr A Youssef Ahmed Abdel-Galeel Department of Cardiovascular Medicine Assiut University Heart HospitalAssiut UniversityAssiut 71526Egypt Department of Cardiology Sohag Heart and GIT CenterSohag 85264Egypt Department of Cardiology Assiut Police HospitalAssiut 71526Egypt Department of Cardiology Qena General HospitalQena 92354Egypt

BACKGROUND Myocardial ischemia and ST-elevation myocardial infarction(STEMI)increase QT dispersion(QTD)and corrected QT dispersion(QTcD),and are also associated with ventricular *** To evaluate the effects of reperfusion strategy[primary percutaneous coronary intervention(PPCI)or fibrinolytic therapy]on QTD and QTcD in STEMI patients and assess the impact of the chosen strategy on the occurrence of in-hospital *** This prospective,observational,multicenter study included 240 patients admitted with STEMI who were treated with either PPCI(group I)or fibrinolytic therapy(group II).QTD and QTcD were measured on admission and 24 hr after reperfusion,and patients were observed to detect in-hospital *** There were significant reductions in QTD and QTcD from admission to 24 hr in both group I and group II *** and QTcD were found to be shorter in group I patients at 24 hr than those in group II(53±19 msec vs 60±18 msec,P=0.005 and 60±21 msec vs 69+22 msec,P=0.003,respectively).The occurrence of in-hospital arrhythmia was significantly more frequent in group II than in group I(25 patients,20.8%vs 8 patients,6.7%,P=0.001).furthermore,QTD and QTcD were higher in patients with in-hospital arrhythmia than those without(P=0.001 and P=0.02,respectively).CONCLUSION In STEMI patients,PPCI and fibrinolytic therapy effectively reduced QTD and QTcD,with a higher observed reduction using *** was associated with a lower incidence of in-hospital arrhythmia than fibrinolytic *** addition,QTD and QTcD were shorter in patients not experiencing in-hospital arrhythmia than those with arrhythmia.

关键词： Arrhythmia QT dispersion ST-segment elevation myocardial infarction Reperfusion Primary percutaneous coronary intervention fibrinolytic therapy