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Ocean stratification and sea-ice cover in Barents and Kara seas modulate sea-air methane flux:satellite data

Advances in Polar Science 2021年第2期32卷 118-140页

作者： Leonid YURGANOV Dustin CARROLL Andrey PNYUSHKOV Igor polyakov Hong ZHANG University of Maryland Baltimore County(ret) BaltimoreMDUSA Moss Landing Marine Laboratories San JoséState UniversityCAUSA International Arctic Research Center University of Alaska FairbanksAKUSA Jet Propulsion Laboratory California Institute of TechnologyCAUSA

The diverse range of mechanisms driving the Arctic amplification and global climate are not completely understood and,in particular,the role of the greenhouse gas methane(CH4)in the Arctic warming remains *** sources of methane at the ocean seabed in the Barents Sea and other polar regions are well ***,some of those publications suggest that negligible amounts of methane fluxed from the seabed enter the atmosphere,with roughly 90%of the methane consumed by *** in situ observations are taken during summer,which is favorable for collecting data but also characterized by a stratified water *** present perennial observations of three Thermal IR space-borne spectrometers in the Arctic between 2002 and *** to estimates derived from the data synthesis ECCO(Estimating the Circulation and Climate of the Ocean),in the ice-free Barents Sea the stratification in winter weakens after the summer strong *** convection,storms,and turbulent diffusion mix the full-depth water ***4 excess over a control area in North Atlantic,measured by three sounders,and the oceanic Mixed Layer Depth(MLD)both maximize in winter.A significant seasonal increase of sea-air exchange in ice-free seas is *** amplitude of the seasonal methane cycle for the Kara Sea significantly increased since the beginning of the *** may be explained by a decline of ice concentration *** annual CH4 emission from the Arctic seas is estimated as 2/3 of land *** Barents/Kara seas contribute between 1/3 and 1/2 into the Arctic seas annual emission.

关键词： satellite data greenhouse gases methane Thermal IR(TIR) Arctic

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On a Perturbation Method for Stochastic Parabolic PDE

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Communications in Mathematics and Statistics 2015年第2期3卷 215-226页

作者： Donald J.Estep Peter L.polyakov Department of Statistics Colorado State University205 Statistics BuildingFort CollinsCO 80523USA Department of Mathematics University ofWyoming1000 EUniversityAveLaramieWY82071USA

In this article,we address two issues related to the perturbation method introduced by Zhang and Lu(J Comput Phys 194:773-794,2004),and applied to solving linear stochastic parabolic *** issues are the construction of... 详细信息

关键词： Stochastic parabolic differential equation Karhunen-Loève expansion

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Variations of the Magnetosphere Resonance Frequencies During Magnetic Storm of July 15-16,2000

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空间科学学报 2005年第5期25卷 387-392页

作者： A. Potapov A. polyakov T. Polyushkina H. Zhao Institute of Solar-Terrestrial Physics Siberia Branch Russian Academy of Sciences Irkutsk 664033 Russia National Microwave Remote Sensing Laboratory Center for Space Science and Applied Research Chinese Academy of Sciences

ULF observations at two mid-latitude sites during the large geomagnetic storm of July 15-16,2000 were used to trace variations of resonance frequencies of the field line resonators. A brief description of the geomagnetic disturbance as it was observed on the ground, at the geostationary orbit, and before the Earth's bow shock is given. Then a detailed study of ULF dynamic spectra from Borok and Mondy is performed for8 succesive 6-hour intervals of July 15 and 16. In conclusion some tasks for the future work are listed.

关键词：等离子体磁场磁气圈空间气候

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A Review of Arctic-Subarctic Ocean Linkages: Past Changes, Mechanisms, and Future Projections

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Ocean-Land-Atmosphere Research 2023年第1期2卷 134-172页

作者： Qiang Wang Qi Shu Shizhu Wang Agnieszka Beszczynska-Moeller Sergey Danilov Laura de Steur Thomas W.N.Haine Michael Karcher Craig M.Lee Paul G.Myers Igor V.polyakov Christine Provost Øystein Skagseth Gunnar Spreen Rebecca Woodgate Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research(AWI) BremerhavenGermany First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdaoPeople’s Republic of China Shandong Key Laboratory of Marine Science and Numerical Modeling QingdaoPeople’s Republic of China Institute of Oceanology Polish Academy of SciencesSopotPoland Department of Mathematics and Logistics Jacobs UniversityBremenGermany Norwegian Polar Institute Fram CentreTromsøNorway Earth&Planetary Sciences The Johns Hopkins UniversityBaltimoreMDUSA .8Ocean Atmosphere Systems GmbH HamburgGermany Applied Physics Laboratory University of WashingtonSeattleWAUSA. Department of Earth and Atmospheric Sciences University of AlbertaEdmontonABCanada. International Arctic Research Center and College of Natural Science and Mathematics University of Alaska FairbanksFairbanksAKUSA. Finnish Meteorological Institute HelsinkiFinland. Laboratoire LOCEAN-IPSL Sorbonne Université(UPMCUniversity Paris 6)CNRSIRDMNHNParisFrance. Institute of Marine Research and Bjerknes Centre of Climate Research BergenNorway. Institute of Environmental Physics University of BremenBremenGermany.

Arctic Ocean gateway fluxes play a crucial role in linking the Arctic with the global ocean and affecting climate and marine *** reviewed past studies on Arctic-Subarctic ocean linkages and examined their changes and driving *** review highlights that radical changes occurred in the inflows and outflows of the Arctic Ocean during the ***,the Pacific inflow temperature in the Bering Strait and Atlantic inflow temperature in the Fram Strait hit record highs,while the Pacific inflow salinity in the Bering Strait and Arctic outflow salinity in the Davis and Fram straits hit record *** the ocean heat convergence from lower latitudes to the Arctic and the hydrological cycle connecting the Arctic with Subarctic seas were stronger in 2000-2020 than in ***6 models project a continuing increase in poleward ocean heat convergence in the 21st century,mainly due to warming of inflow *** also predict an increase in freshwater input to the Arctic Ocean,with the largest increase in freshwater export expected to occur in the Fram Strait due to both increased ocean volume export and decreased *** Strait sea ice volume export hit a record low in the 2010s and is projected to continue to decrease along with Arctic sea ice *** quantitatively attribute the variability of the volume,heat,and freshwater transports in the Arctic gateways to forcing within and outside the Arctic based on dedicated numerical simulations and emphasize the importance of both origins in driving the variability.

关键词： Arctic ocean Strait

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换挡工况下湿式换挡离合器变胞机理

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浙江大学学报（工学版） 2019年第4期53卷 628-637页

作者：符升平李胜波罗宁 Roman Nikolaevich polyakov 厦门理工学院机械与汽车工程学院福建厦门361024 奥廖尔国立大学俄罗斯奥廖尔州302026

针对目前难以全面描述湿式换挡离合器变结构、非定常和非数值的变拓扑工作过程的问题,基于湿式换挡离合器工作特性的分析,定义摩擦对偶片各构态的约束函数,建立摩擦对偶片变胞器,提出湿式换挡离合器变胞的图形描述方法.采用矩阵分析法,... 详细信息

针对目前难以全面描述湿式换挡离合器变结构、非定常和非数值的变拓扑工作过程的问题,基于湿式换挡离合器工作特性的分析,定义摩擦对偶片各构态的约束函数,建立摩擦对偶片变胞器,提出湿式换挡离合器变胞的图形描述方法.采用矩阵分析法,以约束函数为元素,推导离合器各构态的邻接矩阵,解析相邻构态转换时对应的变胞函数和变胞方程,构建湿式换挡离合器工作的变胞拓扑模型,揭示换挡离合器工作状态转换的变胞机理.基于变胞机理分析,提出更直观和简便的离合器动力学建模方法,通过对比分析离合器转速变化规律的试验和仿真结果,表明该方法的准确性和可行性.

关键词：湿式换挡离合器变胞机理约束函数摩擦对偶片变胞方程

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利用地基高分辨率傅里叶变换红外光谱技术探测大气氟氯烃气体CCl_(2)F_(2)的时空变化特征

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物理学报 2021年第20期70卷 3-11页

作者：曾祥昱王薇刘诚单昌功谢宇胡启后孙友文 polyakov Alexander Viktorovich 中国科学院合肥物质科学研究院安徽光学精密机械研究所环境光学与技术重点实验室合肥230031 中国科学技术大学精密机械与精密仪器系合肥230026 合肥学院自动化系合肥230601 Faculty of Physics Saint Petersburg State UniversitySaint Petersburg 199034

大气二氯二氟甲烷(CCl_(2)F_(2),CFC-12)是人工合成的化学制剂,对平流层臭氧可产生严重的破坏和损耗.研究大气CFC-12的探测技术并获取其时空分布和变化,对了解区域氟氯烃气体变化趋势以及对平流层臭氧的影响具有重要意义.本文利用地基... 详细信息

大气二氯二氟甲烷(CCl_(2)F_(2),CFC-12)是人工合成的化学制剂,对平流层臭氧可产生严重的破坏和损耗.研究大气CFC-12的探测技术并获取其时空分布和变化,对了解区域氟氯烃气体变化趋势以及对平流层臭氧的影响具有重要意义.本文利用地基高分辨率傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FTIR)技术研究大气CFC-12的垂直分布和柱浓度的反演方法,基于最优估计算法反演2017-2020年合肥地区大气CFC-12的垂直廓线和柱总量.合肥大气CFC-12反演获得的垂直廓线表明,大气CFC-12在对流层以及低平流层处具有较高浓度,在垂直高度40 km以上浓度极低.合肥地区大气CFC-12的柱浓度含量呈现出夏季浓度较高,冬季与初春浓度较低的季节变化;观测期间大气CFC-12柱浓度呈现缓慢下降的趋势,年均变化率为-0.68%.将地基观测数据与ACE-FTS卫星观测数据进行比对,在高度范围16-28 km内两个CFC-12偏柱总量的相关性系数为0.73,可见地基和卫星数据具有较好的一致性.长期观测结果表明了地基高分辨率FTIR技术在观测大气中CFC-12的浓度垂直分布与季节变化上具有高的准确性和可靠性.

关键词：二氯二氟甲烷太阳吸收光谱柱总量垂直廓线

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Secondary sex ratio of assisted reproductive technology babies

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Asian pacific Journal of Reproduction 2019年第2期8卷 88-92页

作者： Nathira Abdul Majeed Charley Zheng Alex polyakov Megan Pucci Mohamed Hatta Tarmizi Mie Mie Cho Win Royal Women's Hospital MelbourneVictoriaAustralia Royal Women's Hospital and Melbourne IVF MelbourneVictoriaAustralia Oceania University of Medicinea Australia Sabah Women's and Children's Hospital Kota KinabaluSabahMalaysia Obstetrics&Gynaecology Department International Medical SchoolManagement&Science UniversitySelangorMalaysia

Objective: To assess the secondary sex ratio (SSR) of assisted reproduction technology babies within a fertility clinic in Melbourne, Australia. Methods: A retrospective cohort study was conducted on 3369 babies who were born following single embryo transfer between 2011 and 2016. Variables examined included embryo creation date, maternal and paternal ages, maternal body mass index (BMI), type of infertility, sperm parameters, fertilization method, type of embryo and stage of transfer. Multivariate regression analysis was performed on the data set using STRATA V9.2. Results: More males were found to be born to embryos created in summer (adjusted odds ratio=1.46, 95% confidence interval: 1.08-1.95;P=0.01). Lower BMI of mother (≤30 kg/m 2) and younger age of parents (≤35 years) were associated with an increase in SSR (50.1% vs. 47.1%;50.6% vs. 48.8%;50.0% vs. 48.9%) respectively. Decreased SSR value was associated with primary subfertility, using in-vitro fertilization procedure and fresh embryo compared to those with secondary subfertility, using intracytoplasmic sperm injection procedure and thawed embryo (49.3% vs. 50.6%;47.1% vs. 50.8%;49.4% vs. 50.1%) respectively. Conclusions: The fertilization methods, type of embryo, stage of embryo transfer, parameters of the sperm and status of subfertility do not significantly affect the SSR. SSR is affected by the seasonality, maternal age, and BMI.

关键词： Artificial reproduction technology Intracytoplasmic sperm injection In-vitro fertilization Secondary sex ratio

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KF-AlF3-Al2O3熔体和悬浮液中Cu-Al合金的阳极过程

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Transactions of Nonferrous Metals Society of China 2020年第5期30卷 1419-1428页

作者： Sai Krishna PADAMATA Andrey S.YASINSKIY Petr V.polyakov School of Non-Ferrous Metals and Materials Science Siberian Federal UniversityKrasnoyarskRussia

使用计时电位和循环伏安技术表征熔融KF-AlF3-Al2O3(饱和)和悬浮液中Cu-10Al电极阳极过程,证明冰晶石比(CR=x(KF)/x(AlF3))、温度和颗粒体积分数(φ)对阳极电化学行为的影响。最初,在750℃和电流密度为0.4 A/cm^2的条件下,以恒电流模式... 详细信息

使用计时电位和循环伏安技术表征熔融KF-AlF3-Al2O3(饱和)和悬浮液中Cu-10Al电极阳极过程,证明冰晶石比(CR=x(KF)/x(AlF3))、温度和颗粒体积分数(φ)对阳极电化学行为的影响。最初,在750℃和电流密度为0.4 A/cm^2的条件下,以恒电流模式在熔体和悬浮液(φ=0.12,0.15)中进行阳极极化。熔体中的阳极电势在2.5~3.2 V之间变化,悬浮液(φ=0.12)的阳极电势则在3.3~3.4V之间变化。采用XRD分析阳极表面的氧化物相。阳极极限电流密度和传质系数均随着悬浮液中体积分数的增加而急剧下降。研究结果表明,使用Cu-10Al阳极的较好工艺参数是:800℃,熔体CR 1.4,颗粒体积分数约0.09。

关键词：铝悬浮液氧化惰性阳极冰晶石熔体低温电解

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Electron Transport in InN

Electron Transport in InN

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2006 8th International Conference on Solid-State and Integrated Circuit Technology

作者： Frank Schwierz Vladimir M.polyakov Fachgebiet Festkorperelektronik Technische Universitat Ilmenau98684 IlmenauPF 100565Germany

The paper provides an overview on the current understanding of electron transport-in wurtzite Indium Nitride(INN).First,recent findings concerning the bandgap of InN are reviewed and their consequences on electron transport are ***,applying the ensemble Monte Carlo method and new band structure data from the literature,the electron transport in InN is investigated in *** calculate a peak steady-state drift velocity of more than 5×10 cm/s at an electric field of 32 kV/cm,a pronounced transient velocity overshoot, and a remarkably high low-field mobility of 14 000 cm/Vs for undoped *** features of the electron transport in InN are compared to those in other semiconductors and the prospects of InN-based high-speed transistors are addressed.

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根据RSNA共识指南的COVID-19胸部CT典型表现在增长的疫苗接种人群中的真阳性率

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国际医学放射学杂志 2023年第3期 355-356页

作者： N.J.polyakov A.Som N.D.Mercaldo J.D.Capua B.P.Little E.J.Flores 田诗姣

摘要北美放射学会（RSNA）关于新型冠状病毒感染（COVID-19）相关的胸部CT表现的共识指南已被广泛应用。目前尚未有研究评估接种过疫苗的COVID-19肺炎病人中

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