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CO oxidation over ceria supported Au_(22) nanoclusters: Shape effect of the support

Chinese Chemical Letters 2018年第6期29卷 795-799页

作者： Zili Wu David R.Mullins lawrence f.allard Qianfan Zhang Laisheng Wang Chemical Science Division and Center for Nanophase Materials Sciences Oak Ridge National Laboratory Materials Science and Technology Division Oak Ridge National Laboratory Department of Chemistry Brown University

Gold（Au） nanoclusters have recently emerged as ideal models for understanding Au catalysis, because the nanosized Au particles have precise atomic numbers and uniform size. In this work, we studied for the first time the support shape effect on the catalysis of Au nanoclusters by using CO oxidation as a model reaction. Au22（L8）6（L = 1,8-bis（diphenylphosphino） octane） nanoclusters were supported on CeO2 rods or cubes, then pretreated at different temperatures（up to 673 K）, allowing the gradual removal of the organic phosphine ligands. CO oxidation test over these differently pretreated samples shows that CeO2 rods are much better supports than cubes for Au22 nanoclusters in enhancing the reaction rate. In situ IR spectroscopy coupled with CO adsorption indicates that the shape of CeO2 support can impact the nature and quantity of exposed Au sites, as well as the efficiency of organic ligand removal. Although CeO2 rods are helpful in exposing a greater percentage of total Au sites upon ligands removal, the percentage of active Au sites（denoted by Au d＋, 0 〈 d 〈 1） is lower than that on CeO2 cubes. The in situ extended X-ray absorption spectroscopy（EXAfS） and high-angle annular dark-field scanning transmission electron microscopy（HAADf-STEM） results show that the Au nanoclusters bound more strongly to the CeO2 rods than to the cubes where the Au nanoclusters show more sintering. Considering the typical redox mechanism for CO oxidation over supported Au nanoclusters and nanoparticles, it is concluded that the reactivity of the lattice oxygen of CeO2 is the determining factor for CO oxidation over Au22/CeO2. CeO2 rods offer more reactive lattice oxygen and abundant oxygen vacancies than the cubes and thus make the rods a superior support for Au nanoclusters in catalyzing low temperature CO oxidation.

关键词： Gold nanoclusters Ceria Ligands Support shape CO oxidation

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New Insights into the Growth Mechanism and Surface Structure of Palladium Nanocrystals

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Nano Research 2010年第3期3卷 180-188页

作者： Byungkwon Lim Hirokazu Kobayashi Pedro H.G.Camargo lawrence f.allard Jingyue Liu Younan Xia Department of Biomedical Engineering Washington UniversitySt.LouisMissouri 63130USA Materials Science and Technology Division Oak Ridge National LaboratoryOak RidgeTennessee 37831USA Center for Nanoscience and Department of Chemistry and Biochemistry University of Missouri-St.LouisSt.LouisMissouri 63121USA

This paper presents a systematic study of the growth mechanism for Pd nanobars synthesized by reducing Na_(2)PdCl_(4) with L-ascorbic acid in an aqueous solution in the presence of bromide ions as a capping *** electron microscopy(TEM)and high-resolution TEM analyses revealed that the growth at early stages of the synthesis was dominated by particle coalescence,followed by shape focusing via recrystallization and further growth via atomic *** also investigated the detailed surface structure of the nanobars using aberration-corrected scanning TEM and found that the exposed{100}surfaces contained several types of defects such as an adatom island,a vacancy pit,and atomic *** thermal annealing,the nanobars evolved into a more thermodynamically favored shape with enhanced truncation at the corners.

关键词： Palladium nanocrystals growth coalescence surface evolution

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金融界与商业界MBA职业发展的性别差距研究

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新金融 2024年第5期 16-23页

作者： Marianne Bertrand Claudia Goldin lawrence f.Kat 田振(翻译) 缪蛟(翻译) 芝加哥大学哈佛大学不详

Claudia Goldin是2023年诺贝尔经济学奖获得者。2010年,她与Marianne Bertrand和lawrence ***合作在AEJ:Applied Economics发表了此篇文章。该文对美国一所知名商学院MBA的职业生涯进行了调研,以了解MBA不同性别的职业发展。尽管MBA男... 详细信息

Claudia Goldin是2023年诺贝尔经济学奖获得者。2010年,她与Marianne Bertrand和lawrence ***合作在AEJ:Applied Economics发表了此篇文章。该文对美国一所知名商学院MBA的职业生涯进行了调研,以了解MBA不同性别的职业发展。尽管MBA男女在职业生涯初期的收入几乎相同,但他们的收入很快就出现了分化,MBA男性比女性的收入优势在毕业10年后达到了近60个对数点。造成MBA男女收入差距巨大且不断扩大的原因有3个:MBA毕业前培训的差异、职业中断的差异以及每周工作时间的差异。MBA女性的职业生涯中断较多,工作时间较短,这在很大程度上与做母亲有关。当前,帮助不同性别员工获得平等职业发展机会仍然是学术界探讨的重要议题。本刊征得原载期刊同意,编译此文,以飨读者。

关键词：工商管理硕士(MBA) 职业生涯职业中断 MBA男女收入差距

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Current issues in endoscope reprocessing and infection control during gastrointestinal endoscopy

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World Journal of Gastroenterology 2006年第25期12卷 3953-3964页

作者： Douglas B Nelson lawrence f Muscarella Staff Physician in Gastroenterology Minneapolis VA Medical Center University of MinnesotaMinneapolisMN 55417United States Director Research and Development ChiefInfection ControlCustom UltrasonicsInc

The purpose of this article is to review the evidence regarding transmission of infection during gastrointestinal endoscopy, factors important in endoscope reprocessing and infection control, areas to focus on to impr... 详细信息

关键词： Endoscopy Infection Disinfection Reprocessing Infection control

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Delayed peripheral treatment with neurotrophin-3 improves sensorimotor recovery after central nervous system injury

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Neural Regeneration Research 2019年第10期14卷 1703-1704页

作者： Sotiris G.Kakanos lawrence D.f.Moon Neurorestoration Group Wolfson Centre for Age-Related DiseasesKing’s College of London

Neurotrophin-3 (NT3) is a growth factor found in many body tissues including the heart, intestines, skin, nervous system and in skeletal muscles including muscle spindles (Murase et al., 1994). NT3 is required for the survival, correct connectivity and function of sensory (“proprioceptive”) afferents that innervate muscle spindles;these neurons express receptors for NT3 including tropomyocin receptor kinase C. These proprioceptive afferents are important for normal movement (Boyce and Mendell, 2014) and signals from muscle spindles are important for recovery of limb movement (e.g., after spinal cord lateral hemisection)(Takeoka et al., 2014). The level of NT3 declines in most tissues during postnatal development;its level is low in adult and elderly humans and other mammals (Murase et al., 1994). Elevation of NT3 has been shown to improve outcome in various animal models of neurological disease and injury. for example, many groups have shown that delivery of NT3 directly into the central nervous system promotes recovery after spinal cord injury but this often involved invasive routes or gene therapy (Boyce and Mendell, 2014;Petrosyan et al., 2015;Wang et al., 2018).

关键词： Neurotrophin-3(NT3) tissues including the heart Boyce and Mendell

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Seek and Ye Shall [eventually] find： The End of the Search for the Auxin Receptor

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Journal of Integrative Plant Biology 2005年第12期47卷 1412-1417页

作者： lawrence HOBBIE Department of Biology Adelphi University Garden City New York 11530 USA

The mechanism by which the plant hormone auxin regulates gene expression has been shown to involve regulated degradation, through the ubiquitin-proteasome pathway, of transcriptional repressor proteins. However, the key first component in this pathway, the receptor that binds auxin and initiates auxin signaling, has remained a mystery. Two recent papers identify the f-box protein TIR1, part of the complex that attaches ubiquitin to its targets, as an auxin receptor. This breakthrough reveals a new mode of signal transduction and lays the groundwork for a more complete understanding of auxin physiology.

关键词： auxin auxin receptor SCf complex signal transduction ubiquitin.

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foot burns and diabetes: a retrospective study

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Burns & Trauma 2015年第3期3卷 151-154页

作者： E.lawrence f.Li Concord Hospital Burns Unit RhodesAustralia

Background: Diabetes in conjunction with a foot burn can compound the challenges in wound healing;however, the impact of diabetes on outcomes of patients with foot burns has not been examined. Methods: A retrospective notes audit was conducted at the Concord Hospital Burns Unit for patients with foot burns who were admitted from 1st January 2012 to 31st December 2013. Data were collected for 15 subjects with foot burns and diabetes and 18 subjects with foot burns and no diabetes as a control group. Subjects were matched for percentage total body surface area of burns. Results: The mean inpatient and total lengths of stay for the diabetic group were 21.27 days and 64.80 days, which were significantly longer (P = 0.090 and P = 0.054) than the 9.61 days and 30.56 days in the control, based on a significance level of 0.10. The diabetic group was significantly older (P = 0.001), at 56.60 years versus 39.44 years in the control. Significantly (P = 0.033) more patients with diabetes were not working (n = 12/15 or 80.00 % versus n = 7/18 or 38.89 %) compared to the control. The diabetic group had higher rates of regrafting (n = 3/15 or 20.00 % versus n = 1/18 or 5.55 %) than the control and significantly (P = 0.013) more amputations (n = 5/15 or 33.33 % versus n = 0 or 0.00 %) compared to the control. fewer patients with diabetes were prescribed pressure garments (n = 2/15 or 13.33 % versus n = 9/18 or 50.00 %), which was significant (P = 0.034). The increased age of patients in the diabetic group correlates with results from other studies. Healing time may be reflected by total length of stay, which was more than double for patients with diabetes, increasing demand and cost of inpatient and outpatient services. Conclusion: This study highlights the importance of recognizing the potential for poorer outcomes for patients with diabetes and indicates the need for more burn prevention education and promotion in this 'at risk' patient group.

关键词： Diabetes foot Burns Age Regrafting Wound healing

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Computing on Phenotypic Descriptions for Candidate Gene Discovery and Crop Improvement

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Plant Phenomics 2020年第1期2卷 118-121页

作者： Ian R.Braun Colleen f.Yanarella Carolyn J.lawrence-Dill Interdepartmental Bioinformatics and Computational Biology Iowa State UniversityAmesIA 50011USA Department of Genetics Development and Cell BiologyIowa State UniversityAmesIA 50011USA Department of Agronomy Iowa State UniversityAmesIA 50011USA

Many newly observed phenotypes are first described,then experimentally *** language-based descriptions appear in both the literature and in community *** standardize phenotypic descriptions and enable simple data aggregation and analysis,controlled vocabularies and specific data architectures have been *** simplified descriptions have several advantages over natural language:they can be rigorously defined for a particular context or problem,they can be assigned and interpreted programmatically,and they can be organized in a way that allows for semantic reasoning(inference of implicit facts).Because researchers generally report phenotypes in the literature using natural language,curators have been translating phenotypic descriptions into controlled vocabularies for decades to make the information ***,this methodology is highly dependent on human curation,which does not scale to the scope of all publications available across all of plant ***,researchers in other domains have been working to enable computation on natural *** has resulted in new,automated methods for computing on language that are now available,with early analyses showing great *** language processing(NLP)coupled with machine learning(ML)allows for the use of unstructured language for direct analysis of phenotypic ***,we have found that these automated methods can be used to create data structures that perform as well or better than those generated by human curators on tasks such as predicting gene function and biochemical pathway ***,we describe current and ongoing efforts to provide tools for the plant phenomics community to explore novel predictions that can be generated using these *** also describe how these methods could be used along with mobile speech-to-text tools to collect and analyze in-field spoken phenotypic descriptions for association genetics and breedin

关键词： stores translating enable

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On the value distribution of f + a(f')~n

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Science China Mathematics 2008年第7期51卷 1196-1202页

作者： lawrence ZALCMAN Department of Mathematics Bar-Ilan University52900Ramat-GanIsrael

Let f be a transcendental meromorphic function,a a nonzero finite complex number,and n 2 a positive *** f + a(f')n assumes every complex value infinitely *** answers a question of Ye for n = 2.A related normality crit... 详细信息

关键词： meromorphic function value distribution normal families

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Improved prediction of clay soil expansion using machine learning algorithms and meta-heuristic dichotomous ensemble classifiers

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Geoscience frontiers 2022年第1期13卷 268-284页

作者： E.U.Eyo S.J.Abbey T.T.lawrence f.K.Tetteh Department of Geography and Environmental Management University of the West of EnglandBristolUnited Kingdom Research Centre for fluid and Complex Systems Coventry UniversityCoventryUnited Kingdom Department of Civil Engineering University of BirminghamBirminghamUnited Kingdom

Soil swelling-related disaster is considered as one of the most devastating geo-hazards in modern ***,proper determination of a soil’s ability to expand is very vital for achieving a secure and safe ground for ***,this study has provided a novel and intelligent approach that enables an improved estimation of swelling by using kernelised machines(Bayesian linear regression(BLR)&bayes point machine(BPM)support vector machine(SVM)and deep-support vector machine(D-SVM));(multiple linear regressor(REG),logistic regressor(LR)and artificial neural network(ANN)),tree-based algorithms such as decision forest(RDf)&boosted trees(BDT).Also,and for the first time,meta-heuristic classifiers incorporating the techniques of voting(VE)and stacking(SE)were *** independent scenarios of explanatory features’combination that influence soil behaviour in swelling were *** results indicated BLR as possessing the highest amount of deviation from the predictor variable(the actual swell-strain).REG and BLR performed slightly better than ANN while the meta-heuristic learners(VE and SE)produced the best overall performance(greatest R2 value of 0.94 and RMSE of 0.06%exhibited by VE).CEC,plasticity index and moisture content were the features considered to have the highest level of *** binary classifiers(SVM,D-SVM and BPM)gave better accuracy(average accuracy and recall rate of 0.93 and 0.60)compared to ANN,LR and ***-driven diagnostic test indicated that the meta-heuristic models’best performance occurred when ML training was conducted using k-fold validation ***,it is recommended that the concepts developed herein be deployed during the preliminary phases of a geotechnical or geological site characterisation by using the best performing meta-heuristic models via their background coding resource.

关键词： Artificial neural networks Machine learning Clays Algorithm Soil swelling Soil plasticity

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