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聚四氟乙烯-镍化学镀的工艺管理

电镀与环保 1990年第1期10卷 31-35页

作者： david j.sugg 瞿四复美国Techmetals公司

化学镀镍层在解决耐磨、耐腐蚀问题上的优异特性是众所周知的。为了进一步提高这些性能,近年来又在复合镀工艺上进行了探索。在化学镀镍层中共沉积聚四氟乙烯粒子提高了镀层的润滑性与耐磨性。本文集中讨论了可用于控制镀液中聚四氟乙... 详细信息

化学镀镍层在解决耐磨、耐腐蚀问题上的优异特性是众所周知的。为了进一步提高这些性能,近年来又在复合镀工艺上进行了探索。在化学镀镍层中共沉积聚四氟乙烯粒子提高了镀层的润滑性与耐磨性。本文集中讨论了可用于控制镀液中聚四氟乙烯量并测定镀层中聚四氟乙烯量的各种工艺管理技术。

关键词：聚四氟乙烯化学镀镍工艺管理

Analysis of ancient mass extinction recoveries in marine environments: generating strategies for managing outcomes of the current mass extinction

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National Science Review 2024年第1期11卷 8-10页

作者： david j.Bottjer Department of Earth Sciences University of Southern California

The defining feature of a mass extinction and its associated recovery is the global amount of extinction that occurred[1]. However, there is finer-scale detail to the story, as seen in the ongoing modern mass extinction(the sixth mass extinction), which exhibits variable effects among marine ecosystems and environments, and hence geographic areas [1].

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Enhancing diabetic retinopathy screening:Non-mydriatic fundus photography-assisted telemedicine for improved clinical management

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World journal of Diabetes 2024年第8期15卷 1820-1823页

作者： Kira j Szulborski david j Ramsey Department of Ophthalmology Tufts University School of MedicineBostonMA 02111United States Lahey Department of Surgery Division of OphthalmologyUMass Chan Medical SchoolUniversity of MassachusettsBurlingtonMA 01805United States Graduate Faculty New England College of OptometryBostonMA 02115United States

The utilization of non-mydriatic fundus photography-assisted telemedicine to screen patients with diabetes mellitus for diabetic retinopathy provides an accurate,efficient,and cost-effective method to improve early detection of *** has also been shown to correlate with increased participation of patients in other aspects of diabetes *** particular,patients who undergo teleretinal imaging are more likely to meet Comprehensive Diabetes Care Healthcare Effectiveness Data and Information Set metrics,which are linked to preservation of quality-adjusted life years and additional downstream healthcare savings.

关键词： Diabetes Diabetic retinopathy Telemedicine Tele-ophthalmology Nonmydriatic fundus photography-assisted telemedicine Vision screening Preventative health services Health policy

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony R.j.Kucernak david Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOR).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOR activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOR arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

Oryza CLIMtools:A genome–environment association resource reveals adaptive roles for heterotrimeric G proteins in the regulation of rice agronomic traits

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Plant Communications 2024年第4期5卷 145-165页

作者： Angel Ferrero-Serrano david Chakravorty Kobie j.Kirven Sarah M.Assmann Biology Department Pennsylvania State University208 Mueller LaboratoryUniversity ParkPA 16802USA Intercollege Graduate Degree Program in Bioinformatics and Genomics Pennsylvania State University208 Mueller LaboratoryUniversity ParkPA 16802USA

Modern crop varieties display a degree of mismatch between their current distributions and the suitability of the local climate for their *** address this issue,we present Oryza CLIMtools(https://***/CLIMtools/oryza_v1.0/),thefirst resource for pan-genome prediction of climate-associated genetic variants in a crop *** CLIMtools consists of interactive web-based databases that enable the user to(1)explore the local environments of traditional rice varieties(landraces)in South-East Asia and(2)investigate the environment by genome associations for 658 Indica and 283 japonica rice landrace accessions collected from georeferenced local environments and included in the 3K Rice Ge-nomes *** demonstrate the value of these resources by identifying an interplay betweenflowering time and temperature in the local environment that is facilitated by adaptive natural variation in OsHD2 and disrupted by a natural variant in *** quantitative trait locus analysis has suggested the impor-tance of heterotrimeric G proteins in the control of agronomic ***,we analyzed the climate associations of natural variants in the different heterotrimeric G protein *** identified a coordi-nated role of G proteins in adaptation to the prevailing potential evapotranspiration gradient and revealed their regulation of key agronomic traits,including plant height and seed and panicle *** conclude by highlighting the prospect of targeting heterotrimeric G proteins to produce climate-resilient crops.

关键词： Oryza sativa rice G by E adaptation flowering time GWAS OsHD2 OsSOC1 heterotrimeric G pro-tein OsRGA1 d1 OsGS3 OsDEP1 OsGGC2

Integrating petrophysical data into efficient iterative cluster analysis for electrofacies identification in clastic reservoirs

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Energy Geoscience

Energy Geoscience 2024年第4期5卷 291-305页

作者： Mohammed A.Abbas Watheq j.Al-Mudhafar Aqsa Anees david A.Wood Basrah Oil Company BasrahIraq Institute of International Rivers and Eco-Security Yunnan UniversityKunming650500China Institute for Ecological Research and Pollution Control of Plateau Lakes School of Ecology and Environmental ScienceYunnan UniversityKunming650500China DWA Energy Limited LincolnUK

Efficient iterative unsupervised machine learning involving probabilistic clustering analysis with the expectation-maximization(EM)clustering algorithm is applied to categorize reservoir facies by exploiting latent and observable well-log variables from a clastic reservoir in the Majnoon oilfield,southern *** observable well-log variables consist of conventional open-hole,well-log data and the computer-processed interpretation of gamma rays,bulk density,neutron porosity,compressional sonic,deep resistivity,shale volume,total porosity,and water saturation,from three wells located in the Nahr Umr *** latent variables include shale volume and water *** EM algorithm efficiently characterizes electrofacies through iterative machine learning to identify the local maximum likelihood estimates(MLE)of the observable and latent variables in the studied *** optimized EM model developed successfully predicts the core-derived facies classification in two of the studied *** EM model clusters the data into three distinctive reservoir electrofacies(F1,F2,and F3).F1 represents a gas-bearing electrofacies with low shale volume(Vsh)and water saturation(Sw)and high porosity and permeability values identifying it as an attractive reservoir *** results of the EM model are validated using nuclear magnetic resonance(NMR)data from the third studied well for which no cores were *** NMR results confirm the effectiveness and accuracy of the EM model in predicting *** utilization of the EM algorithm for electrofacies classification/cluster analysis is ***,the clusters it establishes are less rigidly constrained than those derived from the more commonly used K-means clustering *** EM methodology developed generates dependable electrofacies estimates in the studied reservoir intervals where core samples are not ***,once calibrated with core data in some wells,the model is suitable for

关键词： Cluster analysis Electrofacies classification Expectation-maximization(EM)algorithm Clastic reservoir Maximum likelihood estimate(MLE)

Extreme Antarctic Cold of Late Winter 2023

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Advances in Atmospheric Sciences 2024年第10期41卷 1873-1880页

作者： Anastasia j.TOMANEK david E.MIKOLAjCZYK Matthew A.LAZZARA Stefano DI BATTISTA Minghu DING Mariana FONTOLAN LITELL david H.BROMWICH Taylor P.NORTON Linda M.KELLER Lee j.WELHOUSE Antarctic Meteorological Research and Data Center Space Science and Engineering CenterUniversity of Wisconsin-MadisonMadisonWisconsin 53706USA Department of Physical Sciences School of EngineeringScienceand MathematicsMadison Area Technical CollegeMadisonWisconsin 53704USA Meteogiornale via Paolo Diacono9Milano 20133Italy State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Byrd Polar and Climate Research Center The Ohio State UniversityColumbusOhio 43210USA Department of Geography The Ohio State UniversityColumbusOhio 43210USA

Extreme cold temperatures were observed in july and August 2023,coinciding with the WINFLY(winter fly-in)period of mid to late August into September 2023,meaning aircraft operations into McMurdo Station and Phoenix Airfield were adversely ***,with temperatures below−50℃,safe flight operation was not possible because of the risk of failing hydraulics and fuel turning to gel onboard the *** cold temperatures were measured across a broad area of the Antarctic,from East Antarctica toward the Ross Ice Shelf,and stretching across West Antarctica to the Antarctic Peninsula.A review of automatic weather station measurements and staffed station observations revealed a series of sites recording new record low *** separate cold phases were identified,each a few days in duration and occurring from mid-july to the end of August 2023.A brief analysis of 500-hPa geopotential height anomalies shows how the mid-tropospheric atmospheric environment evolves in relation to these extreme cold *** monthly 500-hPa geopotential height anomalies show strong negative anomalies in *** of composite geopotential height anomalies during each of the four cold phases suggests various factors leading to cold temperatures,including both southerly off-content flow and calm atmospheric *** the atmospheric environment that leads to such extreme cold temperatures can improve prediction of such events and benefit Antarctic operations and the study of Antarctic meteorology and climatology.

关键词： Antarctica extreme cold temperature automatic weather station networks

Storylines of family medicine Ⅺ:professional identity formation—nurturing one’s own story

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Family Medicine and Community Health 2024年第S3期12卷 99-108页

作者： William B Ventres Leslie A Stone Hamish j Wilson Sumi M Sexton david j Doukas jessica P Cerdena david M Kelley Michael D Fetters jeffrey j Haney john j Frey III Family and Preventive Medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA General Practice and Rural Health University of Otago Dunedin School of MedicineDunedinNew Zealand Family Medicine Georgetown University School of MedicineWashingtonDistrict of ColumbiaUSA Family and Community Medicine Tulane University School of MedicineNew OrleansLouisianaUSA Family Medicine Residency Program Middlesex HealthMiddletownConnecticutUSA Family Medicine University of Michigan Medical SchoolAnn ArborMichiganUSA Medical Education and Clinical Sciences Washington State UniversitySpokaneWashingtonUSA Family Medicine and Community Health University of Wisconsin-Madison School of Medicine and Public HealthMadisonWisconsinUSA

Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅺ:professional identity formation—nurturing one’s own story’,authors address the following themes:‘The social construction of professional identity’,‘On becoming a family physician’,‘What’s on the test?—professionalism for family physicians’,‘The ugly doc-ling’,‘Teachers—the essence of who we are’,‘Family medicine research—it starts in the clinic’,‘Socially accountability in medical education’,‘Personal philosophy and how to find it’and‘Teaching and learning with Storylines of Family Medicine’.May these essays encourage readers to find their own creative spark in medicine.

关键词： own becoming professional

Influence of Local Cation Order on Electronic Structure and Optical Properties of Cation-Disordered Semiconductor AgBiS_(2)

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Chinese Physics Letters 2024年第10期41卷 61-69页

作者： Xiaoyu Wang Muhammad Faizan Yuhao Fu Kun Zhou Yilin Zhang Xin He david j.Singh Lijun Zhang State Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Integrated Optoelectronics Key Laboratory of Automobile Materials of MOECollege of Materials Science and EngineeringJilin UniversityChangchun 130012China Department of Physics and Astronomy University of MissouriColumbiaMissouri 65211-7010USA

Site disorder exists in some practical semiconductors and can significantly impact their intrinsic properties both beneficially and ***,the uncertain local order and structure pose a challenge for experimental and theoretical ***,it hinders the investigation of the effects of the diverse local atomic environments resulting from the site *** employ the special quasi-random structure method to perform first-principles research on connection between local site disorder and electronic/optical properties,using cationdisordered AgBiS_(2)(rock salt phase)as an *** predict that cation-disordered AgBiS_(2)has a bandgap ranging from 0.6 to 0.8 eV without spin-orbit coupling and that spin-orbit coupling reduces this by approximately 0.3 *** observe the effects of local structural features in the disordered lattice,such as the one-dimensional chain-like aggregation of cations that results in formation of doping energy bands near the band edges,formation and broadening of band-tail states,and the disturbance in the local electrostatic potential,which significantly reduces the bandgap and *** influence of these ordered features on the optical properties is confined to alterations in the bandgap and does not markedly affect the joint density of states or optical *** study provides a research roadmap for exploring the electronic structure of site-disordered semiconductor materials,suggests that the ordered chain-like aggregation of cations is an effective way to regulate the bandgap of AgBiS_(2),and provides insight into how variations in local order associated with processing can affect properties.

关键词： stability. structure ordered