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Single cr atom catalytic growth of graphene

Nano research 2018年第5期11卷 2405-2411页

作者： Huy Q. ta Uang zhao Wanjian Yin Darius Pohl Bemd rellinghaus Thomas Gemming Barbara Trzebicka Justinas Palisaitis Gao Jing per O. A. persson zhongfan Liu Alicja Bachmatiuk mark H. rummeli Soochow Institute for Energy and Materials Innovations College of Physics Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow University Suzhou 215005 China Key Laboratory of Advanced Carbon Materials and Wearable Energy Technologies of Jiangsu Province Soochow University Suzhou 215006 China Centre of Polymer and Carbon Materials Polish Academy of Sciences M. Curie-Sklodowskiej 34 Zabrze 41-819 Poland IFW Dresden Helmholtz Strasse 20 01069 Dresden Germany Department of Physics Chemistry and Biology (IFM) Linkoping University SE-581 83 Linkoping Sweden Center for Nanochemistry Beijing Science and Engineering Centre for Nanocarbons Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Single atoms are the ultimate minimum size limit for catalysts. graphene, as an exciting, ultimately thin （one atom thick） material can be imaged in a transmission electron microscope with relatively few imaging artefacts. Here, we directly observe the behavior of single cr atoms in graphene mono- and di-vacancies and, more importantly, at graphene edges. Similar studies at graphene edges with other elemental atoms, with the exception of Fe, show catalytic etching of graphene. Fe atoms have been shown to both etch and grow graphene. In contrast, cr atoms are only observed to induce graphene growth. Complementary theoretical calculations illuminate the differences between Fe and cr, and confirm single cr atoms as superior catalysts for sp^2 carbon growth.

关键词： in situ transmission electron microscope (TEM) electron driven catalysis cr single atom graphene synthesis

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Multifunctional Nanostructured Materials Applied in Controlled radiopharmaceuticals release

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Journal of Biomaterials and Nanobiotechnology 2012年第2期3卷 163-168页

作者： raquel cristina de Sousa Azevedo Daniel crístian Ferreira Soares ricardo Geraldo de Sousa Edésia martins Barros de Sousa Centro de Desenvolvimento da Tecnologia Nuclear(CDTN)/CNEN Serviço de NanotecnologiaBelo HorizonteBrazil Departa-mento de Engenharia Química Universidade Federal de Minas GeraisBelo HorizonteBrazil

The metaiodobenzylguanidine (MIBG) radiopharmaceutical, an analogue of norepinephrine, has been used to diagnose certain diseases in the cardiovascular system when radiolabeled with 123I. This radiopharmaceutical can also be used to treat tumors, such as neuroblastomas and pheochromocytomas, when radiolabeled with 131I. Its clinical use is often accompanied by a slow intravenous administration, where a significant dose of radiation can directly affect workers in nuclear medicine services. To overcome this problem, the incorporation and controlled release of radiopharmaceuticals from the matrix of mesoporous systems based on silica, such as SBA-15 and hybrid [SBA-15/P(N-iPAAm)], can lead to a significant reduction in radiation doses received by workers. In the present study, silica matrices SBA-15 and hybrid [SBA-15/P(N-iPAAm)] containing the radiopharmaceutical MIBG were prepared and physicochemically characterized through FTIr, SEM, and small angle X-ray diffraction techniques. The release profiles of MIBG from SBA-15 and [SBA-15/P(N-iPAAm)] were studied in a simulated body fluid (SBF) to evaluate their potential application as vehicles for controlled releases. Furthermore, in vitro studies were performed to assess the cytotoxicity of matrices as compared to human lung fibroblast cells (MrC-5). The results revealed that the amount of MIBG incorporated within the studied matrices was indeed quite different, showing that only the hybrid [SBA-15/P(N-iPAAm)] system allowed for a more adequate release profile of MIGB. taking all results into consideration, it can be concluded that the hybrid matrix [SBA-15/P(N-iPAAm)] can be considered a potential alternative material for the controlled release delivery of radio-pharmaceuticals.

关键词： SAB-15 Hybrid[SBA-15/P(N-iPAAm)] MIGB radiopharmaceutical Drug release

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Self-reported participation restrictions in normal hearing individuals in thyroid ontogeny: Evidence of subclinical changes

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Journal of Otology 2019年第1期14卷 6-11页

作者： Caio Le?nidas Oliveira de Andrade Gabriela Carvalho Machado Luan Paulo Franco Magalh?es Elen pereira de Jesus Elaine Alves Matias taíse Lima de Oliveira Cerqueira Hélida Braga de Oliveira Luciene da cruz Fernandes Helton Estrela ramos crésio de arag?o Dantas Alves Postgraduate Program in Interactive Processes of Organs and Systems Institute of Health Science–Federal University of Bahia Department of Life Sciences University of the State of Bahia Social Services Sister Dulce Institute of Health Science–Federal University of Bahia Department of Speech Therapy Institute of Health Science–Federal University of Bahia Department of Bioregulation Health & Sciences Institute Federal University Bahia (UFBA) Medical School Institute of Health Science–Federal University of Bahia

Purpose: To verify evidence of subclinical alterations through self-reported participation restrictions in normal hearing individuals and congenital hypothyroidism ***: An analytical, quantitative, cross-sectional exploratory study with a 1:1 ratio, consisting of a convenience sample of 86 normal hearing individuals with(n = 42) and without(n = 44) congenital hypothyroidism diagnosis. All participants underwent tonal and speech audiometry, immitance and distortion product otoacoustic emissions. The researchers excluded people with hearing loss, genetic syndromes and metabolic diseases. The instrument used for evaluate of self-reported participation restrictions was the HHIE-adapted questionnaire, composed of 25 questions, 12 of which were social domain and 13 emotional domain. Student's ttest and chi-square test were used for statistical analysis at a significance level of 5%.results: There was a significant(p reported participation restrictions in CH(61.9%), with a greater relevance for the social domain(p = 0.002). There was a greater frequency of mild/moderate(40.5%)and higher prevalence of association with clinical factors and adherence to ***: The findings indicate that self-reported participation restrictions in normal hearing individuals with congenital hypothyroidism was more significant than in the non-exposed group, suggesting evidence of subclinical auditory abnormalities in this population.

关键词： Hearing Hearing loss Auditory perception Congenital hypothyroidism Surveys and questionnaires

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脂布福吉宁和乙酰毒毛花甙诱发离体浦肯野氏纤维延时性后去极化及触发性心律失常的比较(英文)

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中国药理学报 1994年第2期15卷 97-102页

作者：解景田 Peter CUNNINGHAM Stephen SHOrOFSKY AdrianaMOSCUCCI ChrisCADMAN cr(?)TJANUarY Cardiac Electrophysiology Laboratories. Section of Cardiology Department of Medicine University of Chicago Chicago IL 60637 USA

用细胞外电图信号叠加技术微电极,于羊浦肯野纤维上,比较脂布福吉宁(rBG)(?)乙酰毒毛花甙元(AS)对诱发延时性后去极化(DAD)和触发性心律失常(ta)的作用,结果:1)低中毒剂量于刺激为990和690 ms时诱发出胞内和胞外的DAD;2)高中毒剂量诱发... 详细信息

用细胞外电图信号叠加技术微电极,于羊浦肯野纤维上,比较脂布福吉宁(rBG)(?)乙酰毒毛花甙元(AS)对诱发延时性后去极化(DAD)和触发性心律失常(ta)的作用,结果:1)低中毒剂量于刺激为990和690 ms时诱发出胞内和胞外的DAD;2)高中毒剂量诱发出DAD及ta,包含过早动作电位及触发性心动过速等;3)均引起动作电位振幅、静息电位及最大舒张期电位的降低、50％APD及Q-T间期的缩短,故rBG属于洋地黄类药物。

关键词：毒毛花甙元心律失常浦肯野纤维

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Lamprophyre rocks in the Nassara Gold Deposit, Southwest Burkina Faso: Characteristics and Implication for Mining Exploration

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Open Journal of Geology 2023年第12期13卷 1291-1311页

作者： Pascal Ouiya Adama Ouédraogo Yaméogo Sâga Sawadogo Séta Naba Ecole Normale Supérieure (ENS) Institut Sciences et Technologie (IST) Ouagadougou Burkina Faso Laboratoire Géosciences et Environnement (LaGE) Earth Sciences Department Ouagadougou Burkina Faso University Norbert zONGO (UNz) Koudougou Burkina Faso

The lamprophyres are late dykes that cut the formations hosting the gold mineralization in the Nassara deposit. They are geographically and spatially related to most orogenic gold deposits. It is with the aim of characterizing them and seeing their implications for exploration that this work is carried out. To achieve our objective, petrographic studies and chemical analyses of minerals (pyroxenes, amphiboles, feldspars, chromite) and geochemical analyses of total rock were carried out. These studies have enabled us to classify the Nassara lamprophyres as calc-alkaline lamprophyres of the spessartite type. The cr, Co, Ni and Mg enrichment of these rocks would indicate a depleted mantle source, with LILE enrichment by fluids probably related to metasomatic activity. The various diagrams show that they are depleted in HrEE and enriched in LrEE. The high Nb/ta ratios in our data indicate metasomatic activity probably linked to amphibole and rutile in the mantle prior to melting. The geodynamic context of spessartite-type lamprophyres indicates a signature linked to late-orogenic to post-collisional subduction. They are late-orogenic to post-collisional lamprophyres enriched in compatible elements (cr, Ni, Co) and display a negative ta-Nb-Ti (TNT) anomaly. The frequent association of these lamprophyre dykes with the deposits does not indicate the source of the gold for these deposits, but rather zones of crustal permeability capable of draining hydrothermal fluids at the time of emplacement. Good mapping of lamprophyre dykes, especially in shear zones, could therefore guide prospecting and identify potential zones of hydrothermal fluid circulation.

关键词： Nassara Calc-Alkaline Lamprophyre Metasomatic Activity LILE HrEE LrEE

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Formation of high-silica adakites and their relationship with slab breakoff:Implications for generating fertile Cu-Au-Mo porphyry systems

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Geoscience Frontiers 2024年第6期15卷 454-468页

作者： Fazilat Yousefi David r.Lentz Department of Earth Sciences University of New BrunswickFrederictonNew Brunswick E3B 5A3Canada

In recent years,the characteristics and sources of fertile adakites has received considerable *** well,most recently the geodynamic environment of convergent margins subducting oceanic crust aiding arc formation,evolving to slab rollback,then slab break-off after collision(***-to post-collisional slab failure(arc-like magmatism)and transpression)has gained more recognition,although their relationship to each other has yet to be *** geochemical characteristics imply that adakites/adakite-like,in particular high-silica adakites(HSA),can form by partial melting of subducting hydrothermally altered oceanic crust in convergent plate boundary settings during the terminal stages of subduction,lithosphere thickening,and then failure(all late to post collisional),while the melting of the mantle wedge during subduction-related dehydration creates more typical calc-alkaline basalt-andesite-dacite-rhyolite series(ADr)to form intraoceanic island arc to intracontinental margin arc systems,before the collisional *** are characterized by high-silica(SiO2>67 wt.%),Al2O3>15 wt.%,Sr>300 ppm,Yr/Y(>50),and La/Yb(>10).Some specific geochemical features,such as high Mg#(ave 0.51),Ni(ave 924 ppm),and cr(ave 36 ppm),in HSAs are typical,in contrast to calc-alkaline arcs,although both groups display similar but less pronounced negative anomalies of Nb,ta,and Ti in primitive mantle-normalized trace element spider diagram *** unique geochemical features are likely ascribed to the involvement of garnet,hornblende,and titanite either during partial melting of hydrous MOrB-like oceanic crust with only minor assimilation and fractional crystallization(AFC)within the mantle and crustal during ascent in a transpressional collisional *** for origin of HSA derivative from melting in convergent margins from young,hot oceanic plates subducting into the mantle is applicable to only some a

关键词： High-silica adakites Slab break-off Altered oceanic crust Upwelling asthenosphere Fertile Cu-Au-Mo porphyry systems

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湘江长株潭段底泥重金属污染现状评价

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中南大学学报（自然科学版） 2012年第9期43卷 3710-3717页

作者：朱余银戴塔根吴堑虹中南大学地球科学与信息物理学院湖南长沙410083 西南科技大学环境与资源学院四川绵阳621010

采用地积累指数法和潜在生态危害指数法从不同角度对湘江长株潭段底泥中的重金属污染进行分析评价。研究结果表明:对照全国土壤环境Ⅲ级质量标准和长株潭地区土壤背景值,重金属超标情况类似,Cd,As,zn,Pb和Cu的含量峰值均在霞湾江段;各... 详细信息

采用地积累指数法和潜在生态危害指数法从不同角度对湘江长株潭段底泥中的重金属污染进行分析评价。研究结果表明:对照全国土壤环境Ⅲ级质量标准和长株潭地区土壤背景值,重金属超标情况类似,Cd,As,zn,Pb和Cu的含量峰值均在霞湾江段;各种重金属的污染程度从大到小的排序为:Cd,zn,As,Pb,Ni,Cu和cr;重金属的潜在生态危害系数从大到小的顺序为:Cd,As,Pb,zn,Cu和cr(Pb与zn的相当),其中,Cd的影响起决定作用。

关键词：底泥重金属污染地积累指数潜在生态风险湘江长株潭段

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吡咯亚胺配体与过渡金属的反应性及其催化烯烃聚合

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催化学报 2011年第9期32卷 1439-1445页

作者：苏碧云拓宏兵张群正西安石油大学化学化工学院陕西西安710065

在经典的Brookhart吡啶双亚胺后过渡金属烯烃聚合催化剂基础上,用吡咯五元环代替吡啶六元环骨架可得到具有不同电子效应的新型吡咯亚胺配体.通过吡咯环特殊的电子效应和位阻效应可设计出种类繁多的有别于吡啶亚胺配体的配合物.综述了吡... 详细信息

在经典的Brookhart吡啶双亚胺后过渡金属烯烃聚合催化剂基础上,用吡咯五元环代替吡啶六元环骨架可得到具有不同电子效应的新型吡咯亚胺配体.通过吡咯环特殊的电子效应和位阻效应可设计出种类繁多的有别于吡啶亚胺配体的配合物.综述了吡咯亚胺配体与前过渡金属(Ti,zr等)、后过渡金属(Fe,Co,Ni,Pd等)、稀土金属(Y,Ir,Lu,Nd等)以及其它金属(Cu,U,cr等)的配位方式、配合物的结构类型、反应性及其催化烯烃聚合反应性能.

关键词：吡咯亚胺配体过渡金属配合物烯烃聚合电子效应

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COPEX:co-evolutionary crystal structure prediction algorithm for complex systems

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npj Computational Materials 2021年第1期7卷 1831-1841页

作者： Xiangyang Liu Haiyang Niu artem r.Oganov State Key Laboratory of Solidification Processing International Center for Materials DiscoverySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072P.R.China Skolkovo Institute of Science and Technology Skolkovo Innovation Center30 bldg.1 Bolshoy BoulevardMoscow 121205Russia

crystal structure prediction has been widely used to accelerate the discovery of new materials in recent *** to this day,it remains a challenge to predict the stable stoichiometries and structures of ternary or more complex systems due to the explosive increase of the size of the chemical and configurational *** novel materials with a series of unique characteristics are expected to be found in this virgin territory while new algorithms to predict crystal structures in complex systems are urgently called *** by co-evolution in biology,here we propose a co-evolutionary algorithm,which we name COPEX,and which is based on the well-known evolutionary algorithm *** this proposed algorithm,a few USPEX calculations for ternary systems and multiple for energetically-favored pseudobinary or fixed-composition systems are carried out in parallel,and coevolution is achieved by sharing structural information on the fittest individuals among different USPEX sub-processes during the joint *** have applied the algorithm to W–cr–B,Mg–Si–O,and Hf–ta–C,three very different systems,and many ternary compounds have been *** results clearly demonstrate that the COPEX algorithm combines efficiency and reliability even for complex systems.

关键词： algorithm evolutionary prediction

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Impact of multivitamin and mineral supplements on mortality and nutritional status of hospitalized severely malnourished HIV/AIDS infected children

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Open Journal of Epidemiology 2013年第4期3卷 213-219页

作者： Léon G. Blaise Savadogo Philippe Donnen Fla Kouéta Eléonore Kafando Philippe Hennart Michèle Dramaix cr2-Epidemiology-Biostatistics-Clinical research School of Public Health Université Libre de Bruxelles Bruxelles Belgique Department of Epidemiology and Public Health Child and Mother Health Nutrition and Survival Unit Institut Supérieur des Sci- ences de la Santé Bobo Dioulasso Burkina Faso Pediatric Hospital and University Ouagadougou Burkina Faso

Micronutrient deficiencies, in HIV/AIDS infected children, are common and associated with disease progression and increased mortality. There is no evidence to support specific recommendation for in-patient treatment of severely malnourished HIV/AID infected children. We analyzed the impact of daily oral multivitamin and mineral supplementation on nutritional status and on mortality rate, of severely malnourished HIV/AIDS infected infants, hospitalized in a feeding therapeutic center. Children were randomized at admission in one of the two treatment groups: WHO standard group or additional dose group. The trial has been approved by the national health research ethics committee. Case fatality rate was high in each group. There was no difference in mortality rate between WHO standard group (mortality rate = 16.9%) and “additional dose” group (mortality rate = 17.6%). Kaplan Meir survival curves did not differ between the two groups, (p Log rank = 0.87). During the inpatient follow-up, the median weight gain (g/kg/d) was low in groups and did not differ between WHO standard group (8.88g/kg/d Min = 4.70, Max = 17.23) and “additional dose” group (10.50g/kg/d, Min = 3.29 Max = 17.81) (Wilcoxon test p-value = 0.10). From admission to discharge, anthropometric z-scores means evolution did not differ between the two groups: WHz (p = 0.74), WAz (p = 0.79) and MUAC (p = 0.73). In this randomized trial among severely malnourished HIV/AIDS infected children, we found no evidence that the provision of daily additional micro-nutrient dose during inpatient treatment, compared to WHO standard, improves nutritional status or reduces case fatality rate. rigorous malnutrition inpatient treatments, including effective HIV/AIDS management, improve nutritional status of severely mal-nourished HIV infected children.

关键词： Multivitamin Mortality Nutritional Status Malnourished HIV Children

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