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Electrochemical Realization of 3D Interconnected MoS_(3)/PPy Nanowire Frameworks as Sulfur-Equivalent Cathode Materials for Li-S Batteries

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Energy & Environmental Materials 2024年第2期7卷 9-17页

作者： Hongtao Yu Andreas Siebert Shilin Mei raul garcia-diez Roberto Félix Ting Quan Yaolin Xu Johannes Frisch Regan G.Wilks Marcus Bär Chun Pei Yan Lu Department for Electrochemical Energy Storage Helmholtz-Zentrum Berlin für Materialien und Energie GmbH(HZB)Hahn-Meitner Platz 114109 BerlinGermany Guangdong Province Key Laboratory of Durability for Marine Civil Engineering School of Civil EngineeringShenzhen UniversityShenzhenGuangdong 518060China Department of Interface Design HZBAlbert-Einstein-Str.1512489 BerlinGermany Energy Materials In-Situ Laboratory Berlin(EMIL) Albert-Einstein-Str.1512489 BerlinGermany Helmholtz-Institute Erlangen-Nürnberg for Renewable Energy(HI ERN) Albert-Einstein-Str.1512489 BerlinGermany Department of Chemistry and Pharmacy Friedrich-Alexander-Universität Erlangen-NürnbergEgerlandstr.391058Erlangen Germany Institute of Chemistry University of Potsdam14467Potsdam Germany

The development of freestanding and binder-free electrode is an effective approach to perform the inherent capacity of active materials and promote the mechanism study by minimizing the interference from ***,we construct a freestanding cathode composed of MoS_(3)/PPy nanowires(NWs)deposited on porous nickel foam(NF)(MoS_(3)/PPy/NF)through electrochemical methods,which can work efficiently as sulfur-equivalent cathode material for Li-S *** structural stability of the MoS_(3)/PPy/NF cathode is greatly enhanced due to its significant tolerance to the volume expansion of MoS_(3)during the lithiation process,which we ascribe to the flexible 3D framework of PPy NWs,leading to superior cycling performance compared to the bulk-MoS_(3)/NF *** the interference of binder and carbon additives,the evolution of the chemical and electronic structure of Mo and S species during the discharge/charge was studied by X-ray absorption near-edge spectroscopy(XANES).The formation of lithium polysulfides was excluded as the driving cathode reaction mechanism,suggesting the great potential of MoS_(3)as a promising sulfur-equivalent cathode material to evade the shuttle effect for Li-S *** present study successfully demonstrates the importance of structural design of freestanding electrode enhancing the cycling performances and revealing the corresponding mechanisms.

关键词： 3D-Network electrochemical lithium-sulfur battery MoS_(3) PPy

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Meta-analysis of ground movements associated with deep excavations using a data mining approach

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第2期11卷 409-416页

作者： Harry Holmes Emilio garcia-Taengua raul Fuentes AECOM Ltd. University of Leeds

This paper presents a rigorous statistical approach to identify the controlling factors in the development of ground movements associated with deep excavations. It also gives the most suitable definition of support stiffness from many suggested definitions in the literature. The study is based on a newly compiled database from 389 case studies of propped and anchored excavations. Data mining techniques(e.g. principal component analysis and multi-linear regression) were used to identify significant relationships between the parameters under study and to quantify the global trends in the database. The study shows that the main factors controlling the ground movements are those related to ground conditions, confirming the conclusions of previous empirical studies. It is also shown that the definition of Addenbrooke et al.(1994) is the most suitable expression of support stiffness, therefore providing conclusive evidence for its future use.

关键词： Geomechanics Slope stability Special soil Unsaturated soil

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Fast preparation route to high-performances textured Sr-doped Ca_3Co_4O_9 thermoelectric materials through precursor powder modification

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Science China Materials 2019年第3期62卷 399-406页

作者： Miguel Angel Torres Gustavo garcia Idoia Urrutibeascoa Maria Antonieta Madre Juan Carlos diez Andres Sotelo ICMA (CSIC-Universidad de Zaragoza) Centro Stirling S. Coop. Mondragon Unibertsitatea

This work presents a short and very efficient method to produce high performance textured Ca_3Co_4O_9 thermoelectric materials through initial powders modification. Microstructure has shown good grain orientation, and low porosity while slightly lower grain sizes were obtained in samples prepared from attrition milled powders. All samples show the high density of around 96% of the theoretical *** similar characteristics are reflected in, approximately,the same electrical resistivity and Seebeck coefficient values for both types of samples. However, in spite of similar power factor(PF) at low temperatures, it is slightly higher at high temperature for the attrition milled samples. On the other hand, the processing time reduction(from 38 to 2 h) when using attrition milled precursors, leads to lower mechanical properties in these samples. All these data clearly point out to the similar characteristics of both kinds of samples, with a drastic processing time decrease when using attrition milled precursors, which is of the main economic importance when considering their industrial production.

关键词： ceramics oxides hot-pressing electrical properties power factor

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Temporal-spatial segregation among hummingbirds foraging on honeydew in a temperate forest in Mexico

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Current Zoology 2011年第1期57卷 56-62页

作者： Carlos LARA Vanessa MARTINEZ-garcia raul ORTIZ-PULIDO Jessica BRAVO-CADENA Salvador LORANCA Alex CORDOBA-AGUILAR Laboratorio de Ecologfa de la Conducta Centro Tlaxcala de Biologfa de la Conducta UAT-UNAM Km 1.5 carretera Tlaxcala- Puebla s/n Colonia Xicohtencatl Apdo. Postal 262 Tlaxcala Tlaxcala 90070 Mexico Laboratorio de Ecologfa de Poblaciones. Centro de Investigaciones Biologicas. Universidad Autonoma del Estado de Hidalgo Mexico Departamento de Quimica y Biologia. Universidad de las Ameficas-Puebla. Cholula Puebla Mexico Departamento de Ecologfa Evolutiva. lnstituto de Ecologfa Universidad Nacional Autonoma de Mexico Distrito Federal Mexico

Spatial and temporal variation in interactions between hummingbirds and plants have often been examined, and hummingbirds and insects are known to indirectly interact in networks of nectar plants. In a highland temperate forest in Hidalgo, Mexico some oak trees were heavily infested by honeydew-producing insects （family Margarodidae, tribe Xylococcini, genus Strigmacoccus） and the honeydew was consumed by hummingbirds. Here using survival analysis we investigate how the honey- dew produced by dense populations of these margarodids is temporally and spatially partitioned by hummingbirds. We also measured the availability and quality of honeydew exudates, and then we recorded the time until a bird visited and used such re- sources. Four hummingbird species consumed this resource （Atthis eloisa, Hylocharis leucotis, Colibri thalassinus and Eugenes fulgens）. Data from 294 hours of observation on seven focal trees suggested temporal and spatial segregation among visiting birds according to body size and territorial behavior during the most honeydew-limited time. Hummingbird species differed in the dally times they foraged, as well as in the location where honeydew-producing insects were visited on the trees. Temporal and spatial segregation among hummingbird species is interpreted as an adaptation to reduce the risk of aggressive encounters. This may facilitate multispecies coexistence and allow these birds to exploit honeydew more effectively

关键词： Honeydew Hummingbirds Mexico Nectarivory Niche partitioning

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Planetary Gear Profile Modification Design Based on Load Sharing Modelling

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Chinese Journal of Mechanical Engineering 2015年第4期28卷 810-820页

作者： IGLESIAS Miguel FERNáNDEZ DEL RINCóN Alfonso DE-JUAN Ana Magdalena garcia Pablo diez Alberto VIADERO Fernando Mechanical Engineering Research Group University of Cantabria

In order to satisfy the increasing demand on high performance planetary transmissions, an important line of research is focused on the understanding of some of the underlying phenomena involved in this mechanical system. Through the development of models capable of reproduce the system behavior, research in this area contributes to improve gear transmission insight, helping developing better maintenance practices and more efficient design processes. A planetary gear model used for the design of profile modifications ratio based on the levelling of the load sharing ratio is presented. The gear profile geometry definition, following a vectorial approach that mimics the real cutting process of gears, is thoroughly described. Teeth undercutting and hypotrochoid definition are implicitly considered, and a procedure for the incorporation of a rounding arc at the tooth tip in order to deal with corner contacts is described. A procedure for the modeling of profile deviations is presented, which can be used for the introduction of both manufacturing errors and designed profile modifications. An easy and flexible implementation of the profile deviation within the planetary model is accomplished based on the geometric overlapping. The contact force calculation and dynamic implementation used in the model are also introduced, and parameters from a real transmission for agricultural applications are presented for the application example. A set of reliefs is designed based on the levelling of the load sharing ratio for the example transmission, and finally some other important dynamic factors of the transmission are analyzed to assess the changes in the dynamic behavior with respect to the non-modified case. Thus, the main innovative aspect of the proposed planetary transmission model is the capacity of providing a simulated load sharing ratio which serves as design variable for the calculation of the tooth profile modifications.

关键词： transmission planetary gear load sharing relief profile modification

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Etching-free pixel definition in InGaN green micro-LEDs

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Light(Science & Applications) 2024年第8期13卷 1655-1665页

作者： Zhiyuan Liu Yi Lu Haicheng Cao Glen Isaac Maciel garcia Tingang Liu Xiao Tang Na Xiao raul Aguileta Vazquez Mingtao Nong Xiaohang Li Advanced Semiconductor Laboratory Electrical and Computer Engineering ProgramCEMSE DivisionKing Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Kingdom of Saudi Arabia

The traditional plasma etching process for defining micro-LED pixels could lead to significant sidewall *** near sidewall regions act as non-radiative recombination centers and paths for current leakage,significantly deteriorating device *** this study,we demonstrated a novel selective thermal oxidation(STO)method that allowed pixel definition without undergoing plasma damage and subsequent dielectric *** annealing in ambient air oxidized and reshaped the LED structure,such as p-layers and InGaN/GaN multiple quantum ***,the pixel areas beneath the pre-deposited SiO_(2)layer were selectively and effectively *** was demonstrated that prolonged thermal annealing time enhanced the insulating properties of the oxide,significantly reducing LED leakage ***,applying a thicker SiO_(2)protective layer minimized device resistance and boosted device efficiency *** the STO method,InGaN green micro-LED arrays with 50-,30-,and 10-μm pixel sizes were manufactured and *** results indicated that after 4 h of air annealing and with a 3.5-μm SiO_(2)protective layer,the 10-μm pixel array exhibited leakage currents density 1.2×10^(-6)A/cm^(2)at-10 V voltage and a peak on-wafer external quantum efficiency of~6.48%.This work suggests that the STO method could become an effective approach for future micro-LED manufacturing to mitigate adverse LED efficiency size effects due to the plasma etching and improve device ***-LEDs fabricated through the STO method can be applied to micro-displays,visible light communication,and optical interconnect-based *** planar pixel geometry will provide more possibilities for the monolithic integration of driving circuits with ***,the STO method is not limited to micro-LED fabrication and can be extended to design other III-nitride devices,such as photodetectors,laser diodes,high-electron-mobility transistors

关键词： annealing protective quantum

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Postural control quantification in minimally and moderately impaired persons with multiple sclerosis:The reliability of a posturographic test and its relationships with functional ability

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Journal of Sport and Health Science 2020年第6期9卷 677-684页

作者： David Barbado Ramon Gomez-Illan Pedro Moreno-Navarro Gregori Valero-Conesa raul Reina Francisco J.Vera-garcia Department of Sport Sciences Sports Research CentreMiguel Hern_andez University of ElcheElche(Alicante)03202Spain

Background:Postural control has been associated with the functional impairment in persons with multiple sclerosis(pwMS).However,there is a need for reliable methods to assess postural control in early stages of the disease,when subtle changes can be difficult to *** aims of this study were to assess the absolute and relative reliability of a standing and a sitting posturographic protocol in minimally(Expanded Disability Status Scale≤2)and moderately(2.5≤Expanded Disability Status Scale≤4)impaired pwMS,and to analyze relationships among postural control and functional mobility and gait ***:To assess postural control in an upright stance,14 minimally and 16 moderately impaired pwMS performed six 70 s trials in tandem stance,3 with their weaker leg behind(TSWL)and 3 with their stronger leg behind(TSSL).Additionally,participants completed five 70 s trials using an unstable sitting protocol(US)to assess trunk *** mean radial errors of TSWL,TSSL,and US trials were calculated as postural control ***,participants performed the Timed Up and Go test(TUG)and the Timed 25-foot Walk test(T25FW)to measure their functional mobility and gait speed,*** was evaluated using the intraclass correlation coefficient(ICC3,1)and the standard error of measurement(SEM).Analyses of variances were carried out to assess between-group ***’g index(dg)was used to estimate the effect size of *** correlation analyses(r)were performed to examine the relationships among the postural control and the functional ***:Posturographic tests showed a high reliability in both minimally(0.87≤ICC≤0.92;9.32%≤SEM≤11.76%)and moderately(0.80≤ICC≤0.92;10.33%≤SEM≤15.33%)impaired ***,T25FW and TUG displayed a high consistency in minimally(0.89≤ICC≤0.94;3.43%≤SEM≤5.17%)and moderately(0.85≤ICC≤0.93;5.57%≤SEM≤6.56%)impaired *** impaired pwMS showed a better performance on the TUG,T25FW

关键词： Balance Consistency of the assessment Core stability Functional mobility

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Pneumo-CT assessing response to neoadjuvant therapy in esophageal cancer: Imaging-pathological correlation

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World Journal of Gastrointestinal Oncology 2013年第12期5卷 222-229页

作者： Marina Ulla Ernestina Gentile Ezequiel Levy Yeyati Maria L diez Demetrio Cavadas Ricardo D garcia-Monaco Pablo R Ros Department of Radiology Hospital Italiano de Buenos Aires

Pneumo-computed tomography (PnCT) is a technique primarily developed and used to study stenotic lesions of the esophagus, gastroesophageal junction and stom-ach for pre-surgical planning. It helps to define both upper and lower borders of neoplasms located in the aforementioned areas. It achieves maximum lumen distension with CO2 highlighting thickened areas of the esophageal wall, thus allowing an accurate quantifica-tion of their extents. Although there are other alterna-tives for distension (oral contrast agents, water and ef-fervescent granules), they may be suboptimal. Patients with locally advanced esophageal cancer have a dismal prognosis despite surgical resection. Therefore, neo-adjuvant treatment strategies using radiation therapy and chemotherapy were developed to improve sur-vival. Neoadjuvant therapy improves esophageal tumor prognosis in a substantial proportion of patients, and the use of imaging techniques is mandatory to detect their response. PnCT combined with virtual endoscopy and multiplanar reconstruction enhances morphologic details in esophageal cancer, and thus would allow animproved assessment of response to neoadjuvant treat-ment. Therefore, more information could be provided to assess the efficacy of pre-surgical treatment. We de-scribe the potential use of PnCT to assess the response to neoadjuvant therapy in esophageal cancer with an imaging pathologic correlation.

关键词： Esophagus Cancer 64-multidetector com-puted tomography Neoadjuvant treatment Assess-ment response

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Evaluation of VEGF gene polymorphisms and proliferative diabetic retinopathy in Mexican population

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International Journal of Ophthalmology(English edition) 2017年第1期10卷 135-139页

作者： Roberto Gonzalez-Salinas Maria C garcia-Gutierrez Gerardo garcia-Aguirre Virgilio Morales-Canton raul Velez-Montoya Vidal R Soberon-Ventura Victoria Gonzalez Rodrigo Lechuga Pablo garcia-Solis David G garcia-Gutierrez Marco Vinicio garcia-Solis Manuel Saenz de Viteri Juan C Solis-S Biomedical Research Department Autonomous University of QueretaroQueretaro 76170Mexico Retina Department Asociation to Prevent Blindness in MexicoMexico City 04030Mexico Research Department Asociation to Prevent Blindness in MexicoMexico City 04030Mexico Retina Department General Hospital of Queretaro(ISSSTE)Queretaro 76000Mexico Universidad La Salle School of Medicine Mexico City 06140Mexico

AIM： To assess if the included vascular endothelial growth factor （VEGF） polymorphisms rs3025035, rs3025021 and rs2010963 are associated to proliferative retinopathy in a Mexican population with type 2 diabetes mellitus （T2DM）. METHODS： A case-control study was conducted in adult individuals with T2DM associated to proliferative retinopathy or non-proliferative retinopathy from Oct. 2014 to Jun. 2015 from the Retina Department of the Asociation to Prevent Blindness in Mexico. The selected patients were adults with a diagnosis of T2DM ≥5y. All subjects had a comprehensive ocular examination and the classification of the retinopathy severity was made considering the Early Treatment Diabetic Retinopathy Study （ETDRS） standardization protocols. Genomic DNA was extracted from whole fresh blood. All samples were genotyped by qPCR for selected VEGF polymorphisms. Hardy-Weinberg equilibrium was calculated by comparing Chi-square values between the expected and the observed values for genotype ***： In total 142 individuals were enrolled, 71 individuals with T2DM and associated proliferative retinopathy and 71 individuals with non-proliferative retinopathy. One-sided Fisher’s exact test was performed for rs3025021 [OR （95% CI）=0.44（0.08-2.2）; P=0.25] and rs2010963 [OR （95% CI）=0.63（0.25-1.6）; P=0.23]. The minor allelic frequencies obtained were 26% for rs3025021, 10% for rs3025035 and 61% for rs2010963. The pairwise linkage disequilibrium between the three SNP was assessed, and was as follows： rs3025021 vs rs3025035： D’=1.0, r2=0.1043, P≤0.0001; rs3025021 vs rs2010963： D’=0.442, r2=0.0446, P=0.149; rs3025035 vs rs2010963： D’=0.505, r2=0.0214, P=***： This is the first analysis involving VEGF polymorphisms and proliferative diabetic retinopathy in a Mexican population. A major finding of the present study is that none of the polymorphisms studied was significantly associated with proliferative retinopathy. Based on these results, we can infer that differ

关键词： vascular endothelial growth factor polymor-phism proliferative diabetic retinopathy non-proliferative diabetic retinopathy rs3025021 rs3025035 rs2010963

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Repeatability of in-vitro optical quality measurements of intraocular lenses with a deflectometry technique effect of the toricity

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International Journal of Ophthalmology(English edition) 2018年第7期11卷 1139-1144页

作者： Teresa Ferrer-Blasco Alberto Dominguez-Vicent Santiago garcia-Lazaro Maria Amparo diez-Ajenjo Jose F.Alfonso Jose J.Esteve-Taboada Department of Optics and Optometry and Visual Science University of Valencia Valencia 46100 Spain Clinica Optometrica Fundacio Lluis Alcanyis Universitat de Valencia Valencia 46020 Spain Surgery Department Fernandez-Vega Ophthalmological Institute Oviedo 33012 Spain School of Medicine University of Oviedo Oviedo 33006 Spain

AIM： To evaluate the repeatability of an optical device for measuring the Zernike coefficients of toric intraocular lenses（IOLs） and assess whether its toricity has any impact in its repeatability. METHODS： An experienced technician used the NIMO TR1504 to measure the Zernike coefficients 30 times for an aperture of 4.50 mm for all lenses included. The IOLs included were divided into two group： toric and nontoric ones. The cylindrical powers of the toric lenses included in the present study were 1.00, 1.50, 2.25, 3.00 and 3.75 D. Finally, the repeatability of the NIMO TR1504 was described in terms of within subject standard deviation（Sw） and repeatability limit. RESULTS： The Sw was smaller than 0.011 μm for both lens groups and all Zernike coefficients, and the difference between both groups was smaller than 0.004 μm for all Zernike coefficients. Regarding the repeatability limit, this value was smaller than 0.025 μm for the toric lens group, and smaller than 0.031 μm for the non-toric lens one for all Zernike coefficients. Furthermore, the maximum difference between both lens groups was 0.010 μm. CONCLUSION： The repeatability of the NIMO TR1504 to measure the optical quality is high and independent of the lens toricity. These results reflect that this system is robust and could be used to measure the in-vitro optical quality of either toric or non-toric IOLs.

关键词： in-vitro measurements optical quality intraocular lens repeatability

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