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Journal of Materials Science and Chemical Engineering 2022年第10期10卷 1-9页

作者： Viviane Pestano mariana pohlmann Fabio Pinto da Silva Design and Materials Selection Lab Postgraduate Program in Design Federal University of Rio Grande do Sul Porto Alegre Brazil

FDM is a widely used additive manufacturing process, however, it has some limitations, such as surface finish, due to the staircase effect caused by the layer-by-layer deposition. Studies have been conducted on surface finish of ABS parts with the use of acetone, but the process parameters and the resulting effects have not been fully investigated in the literature. Therefore, the aim of this study was to investigate the effects of acetone vapor smoothing process on surface finish and geometric accuracy of fused deposition modeling ABS parts. Specimens with different geometries were created and printed using two directions in different scales. The parts were exposed to acetone vapor for 20, 30 and 40 minutes. 3D deviation maps, roughness and microscopic analyses were conducted. The staircase effect was reduced at the expense of some geometric deviations, which varied according to the exposure time and part orientation. The smoothing process applied to the flat surfaces proved to be quite effective in reducing roughness by 90%, however, this reduction led to an undesirable rounding of the sharp edges. The results obtained in this study are consistent with those found in the literature and may help improve the quality of the ABS printed parts.

关键词： Additive Manufacturing 3D Printing FDM Staircase Effect Acetone Vapor Polishing

Omicron:Master of immune evasion maintains robust ACE2 binding

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Signal Transduction and Targeted Therapy 2022年第5期7卷 1360-1362页

作者： Markus Hoffmann Lu Zhang Stefan pohlmann Infection Biology Unit German Primate Center—Leibniz Institute for Primate ResearchGöttingenGermany Georg-August-University Göttingen GöttingenGermany

The spike(S)protein of the SARS-CoV-2 Omicron variant is highly mutated but the impact of these mutations on viral entry into cells and its inhibition by antibodies has been unclear.A recent study published in Science by Mannar et *** shows that these mutations are compatible with robust ACE2 binding and allow for efficient evasion of neutralizing *** emergence of SARS-CoV-2 variants has become a hallmark of the COVID-19 *** of concern(VOC)harbor mutations in the viral S protein that can increase transmissibility,potentially by promoting S protein binding to the cellular receptor ACE2.

关键词： ACE2 maintain

Assimilation of surface currents into a regional model over Qingdao coastal waters of China

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Acta Oceanologica Sinica 2013年第7期32卷 21-28页

作者： ZHAO Jian CHEN Xueen XU Jiangling HU Wei CHEN Jinrui pohlmann Thomas College of Physical and Environmental Oceanography Ocean University of China North China Sea Brach State Oceanic Administration University of Hamburg

Surface currents measured by high frequency （HF） radar arrays are assimilated into a regional ocean model over Qingdao coastal waters based on Kalman filter method. A series of numerical experiments are per- formed to evaluate the performance of the data assimilation schemes. In order to optimize the analysis pro- cedure in the traditional ensemble Kalman filter （ENKF）, a different analysis scheme called quasiensemble Kaman filter （QENKF） is proposed. The comparisons between the ENKF and the QENKF suggest that both them can improve the simulated error and the spatial structure. The estimations of the background error covariance （BEC） are also assessed by comparing three different methods： Monte Carlo method; Canadian quick covariance （CQC） method and data uncertainty engine （DUE） method. A significant reduction of the root-mean-square （RMS） errors between model results and the observations shows that the CQC method is able to better reproduce the error statistics for this coastal ocean model and the corresponding external forcing. In addition, the sensibility of the data assimilation system to the ensemble size is also analyzed by means of different scales of the ensemble size used in the experiments. It is found that given the balance of the computational cost and the forecasting accuracy, the ensemble size of 50 will be an appropriate choice in the Qingdao coastal waters.

关键词： Qingdao coastal waters surface currents Ensemble Kalman filter Finite Volume Coastal OceanModel (FVCOM)

Mutation D614G increases SARS-CoV-2 transmission

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Signal Transduction and Targeted Therapy 2021年第4期6卷 1075-1076页

作者： Prerna Arora Stefan pohlmann Markus Hoffmann Infection Biology Unit German Primate CenterGottingenGermany Faculty of Biology and Psychology Georg-August-University GottingenGottingenGermany

It has been unclear why SARS-CoV-2 with a D614G mutation in the spike protein became dominant early in the COVID-19 pandemic.A recent study by Hou et *** in Science shows that D614G increases SARS-CoV-2 spread in cult... 详细信息

关键词： 4G D61 spread

A novel high resolution model without open boundary conditions applied to the China Seas: first investigation on tides

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Acta Oceanologica Sinica 2010年第6期29卷 12-25页

作者： YU Huaming CHEN Xueen BAO Xianwen Thomas pohlmann WU Dexing Institute of Physical Oceanography Ocean University of China Qingdao 266100 China Institute of Oceanography Centre for Marine and Climate Research University of Hamburg Hamburg 20146 Germany

We developed a Global Ocean Circulation and Tide Model （GOCTM） with coarse grids in the open deep ocean degrading ‘smoothly’ into the highly resolved China Seas （CS） of refined grids to study the tides and circulation *** is based on the framework of the Finite Volume approach for better mass conservation through improved transports across the discrete individual control *** also takes a full advantage of the geometric flexibility of unstructured mesh using a realistic global topography including the Arctic *** CS are given a special focus by refining the unstructured grids,but they are embedded into global domain ***,GOCTM not only successfully avoids the treatment of the open boundaries,but also optimizes the trade-off between computational cost and model ***,GOCTM is driven by the astronomical tide-generating potential and the secondary tide-generating potential directly,together with the wind stress and heat *** succeeds in reproducing the global eight principal tidal harmonic ***,the simulated tidal results in the CS are improved compared to some other regional models with the discrepancy of 3.9 cm for M 2 *** idea of GOCTM can also be referred for other regional ocean study.

关键词： finite volume model GOCTM open boundary conditions the China Seas

Intrahepatic distribution of hepatitis B virus antigens in patients with and without hepatocellular carcinoma

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World Journal of Gastroenterology 2016年第12期22卷 3404-3411页

作者： Parham Safaie Mugilan Poongkunran Ping-Ping Kuang Asad Javaid Carl Jacobs Rebecca pohlmann Imad Nasser Daryl TY Lau Liver Center Division of Gastroenterology Department of Medicine Beth Israel Deaconess Medical Center Harvard Medical School Department of Pathology Beth Israel Deaconess Medical Center Harvard Medical School

AIM: To study the intrahepatic expression of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in chronic hepatitis B patients with and without hepatocellular ***: A total of 33 chronic hepatitis B patients (mean age of 40.3 ± 2.5 years), comprising of 14 HBeAg positive and 19 HBeAg negative patients; and 13 patients with hepatitis B virus related hepatocellular carcinoma (mean age of 49.6 ± 4.7 years), were included in our study. Immunohistochemical staining for HBcAg and HBsAg was done using standard streptavidin-biotin-immunoperoxidase technique on paraffin-embedded liver biopsies. The HBcAg and HBsAg staining distributions and patterns were described according to a modified classification ***: Compared to the HBeAg negative patients, the HBeAg positive patients were younger, had higher mean HBV DNA and alanine transaminases levels. All the HBeAg positive patients had intrahepatic HBcAg staining; predominantly with “diffuse” distribution (79%) and “mixed cytoplasmic/nuclear” pattern (79%). In comparison, only 5% of the HBeAg-negative patients had intrahepatic HBcAg staining. However, the intrahepatic HBsAg staining has wider distribution among the HBeAg negative patients, namely; majority of the HBeAg negative cases had “patchy” HBsAg distribution compared to “rare” distribution among the HBeAg positive cases. All but one patient with HCC were HBeAg negative with either undetectable HBV DNA or very low level of viremia. Intrahepatic HBcAg and HBsAg were seen in 13 (100%) and 10 (77%) of the HCC patients respectively. Interestingly, among the 9 HCC patients on anti-viral therapy with suppressed HBV DNA, HBcAg and HBsAg were detected in tumor tissues but not the adjacent liver in 4 (44%) and 1 (11%) patient ***: Isolated intrahepatic HBcAg and HBsAg can be present in tumors of patients with suppressed HBV DNA on antivir

关键词： Hepatitis B virus Chronic hepatitis B Hepatocellular carcinoma Hepatitis B core antigen Hepatitis B surface antigen

Organophosphate Esters in Air and Seawater of the South China Sea:Spatial Distribution,Transport,and Air−Sea Exchange

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Environment & Health 2023年第3期1卷 191-202页

作者： Lijie Mi Zhiyong Xie Lulu Zhang Joanna J.Waniek Thomas pohlmann Wenying Mi Weihai Xu Institute of Coastal Environmental Chemistry Helmholtz-Zentrum HereonGeesthacht 21502Germany Institute of Oceanography University of HamburgHamburg 20146Germany Key Laboratory of Ocean and Marginal Sea Geology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Sanya Institute of Ocean Eco-Environmental Engineering Sanya 572000China University of Chinese Academy of Sciences Beijing 100049China Department of Marine Chemistry Leibniz Institute for Baltic Sea Research WarnemündeRostock 18119Germany MINJIE Institute of Environmental Science and Health Research Geesthacht 21502Germany

Organophosphate esters(OPEs)have become one group of chemicals with emerging concern in the marine *** this work,we investigated OPEs in the air and seawater of the South China Sea in summer *** concentrations of∑_(10)OPEs in the atmosphere ranged from 66 to 550 pg/m^(3),with TCIPP,TNBP,TPhP,and TEP predominating in the *** total dissolved OPE concentrations(∑_(10)OPEs without TEP)measured in high-volume water samples ranged from 300 to 3600 pg/L,with a mean concentration of 1180±910 pg/*** was measured with liquid−liquid extraction(LLE),and it showed the highest concentration(average 2000±1450 pg/L)among the selected *** suspended matter associated OPEs accounted for less than 4.7%of the sum of OPE concentrations in *** fractions and air−sea exchange fluxes showed that TCEP,TCIPP,TIBP,TEHP,TPhP,and EHDPP were favored to volatilize,TEP dominated the deposition,while TPrP and TNBP varied between volatilization and *** particle deposition fluxes ranged from 5 to 71 ng/m^(2)/day with an average of 17±15 ng/m^(2)/*** input of∑OPEs to the entire South China Sea via atmospheric particle deposition was estimated to be 22±19 tons/year,while the net air−sea exchange fluxes of OPEs were volatilization from seawater to air with an average of 44±33 tons/*** work suggests that air−sea exchange and atmospheric particle deposition are significant processes interfering with the transport of OPEs in the marine environment.

关键词： Organophosphate esters South China Sea Air−sea exchange Atmospheric deposition Long-range transport

原始热通量资料的海陆分布对近海SST模拟的影响

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中国海洋大学学报（自然科学版） 2010年第7期40卷 24-28页

作者：宋丹 Thomas pohlmann 陈学恩中国海洋大学物理海洋实验室山东青岛266100 德国汉堡大学海洋研究所德国汉堡d20146

对于海洋数值模式用以计算海表温度(SST)的热通量资料,本文在插值的过程中引入了1个权重因子f,以探讨由于原始资料和数值模式的分辨率以及相应的海陆分布的不同所导致的近海SST模拟误差。对于原始资料中坐标位于海洋的点,f_O=1.0;而对... 详细信息

对于海洋数值模式用以计算海表温度(SST)的热通量资料,本文在插值的过程中引入了1个权重因子f,以探讨由于原始资料和数值模式的分辨率以及相应的海陆分布的不同所导致的近海SST模拟误差。对于原始资料中坐标位于海洋的点,f_O=1.0;而对于坐标位于陆地的点,f_L～[0,1]。数值实验对比了渤海和北黄海的原始数据插值结果和SST模拟结果。通过对比数值模式和原始资料的海陆分布,发现在模拟海区有相当多的模式水点被原始资料的陆点半围绕,在这些点上的插值结果受f_L的取值影响较大。本文的对比数值实验表明,当f_L分别取0.5和1.0时,对SST的模拟差异在部分海域达到了O(0.1℃)的量级,与数值模式本身的误差量级相当,是海洋数值研究中应当给予重视的误差因素。

关键词：热通量资料海陆分布权重因子海表温度

The influence of the Three-Gorges Dam on hydrographic and hydrodynamic conditions of the East China Sea

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Acta Oceanologica Sinica 2011年第5期30卷 45-55页

作者： FAN Xiaopeng ZHOU Feng CHEN Xueen HUANG Daji pohlmann Thomas State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Institute of Physical Oceanography Ocean University of China Qingdao 266002 China Institute of Oceanography University of Hamburg Hamburg 20146 Germany Department of Ocean Science and Engineering Zhejiang University Hangzhou 310058 China

A fine resolution model has been applied to get more insight into the effects of a modified runoff due to the Three-Gorges-Dam （TGD） on the East China Sea （ECS）.The region of interest was confined to the offshore area in the vicinity of the Changjiang *** the east,it extended up to the area southwest of Cheju *** model was used to evaluate the effect of a modified runoff on the water properties of the adjacent regions like the Changjiang diluted water （CDW） and the Zhoushan Fishing *** sensitivity of the ECS to a modified Changjiang runoff was explored firstly by sensitivity studies and secondly by experiments based on historical runoff records and water management plans of the *** experiments led to the general conclusion that the most affected area by runoff is located close to the Changjiang River *** area of influence has an extension of about 150 km×150 *** the realistic experiment,the related anomalies reached their maximum value in early summer （May）.In normal years the related salinity anomalies can get to as large as 2.

关键词： Three-Gorges-Dam surface salinity anomalies stratification East China Sea

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渤海环流与输运季节变化的数值模拟(英文)

黄渤海海洋 2001年第2期19卷 1-9页

作者：魏皓武建平 pohlmann Thomas 青岛海洋大学物理海洋研究所山东青岛266003 国家海洋局第一海洋研究所山东青岛266061 Institute of Oceanology

渤海的风和温度层结有明显的季节变化 ,因而其环流与输运亦有明显的季节信号。以季节平均的海面气象条件和开边界的潮波系统驱动三维斜压水动力模型———HAMSOM ,模拟了渤海冬、夏季的总环流。渤海环流冬强夏弱 ,表层风漂流常被下层逆... 详细信息

渤海的风和温度层结有明显的季节变化 ,因而其环流与输运亦有明显的季节信号。以季节平均的海面气象条件和开边界的潮波系统驱动三维斜压水动力模型———HAMSOM ,模拟了渤海冬、夏季的总环流。渤海环流冬强夏弱 ,表层风漂流常被下层逆风流所补偿。深度平均环流 ,即水柱内的输运 ,流型有显著的季节变化 :冬季在渤海中部沿逆时针方向旋转 ,辽东湾顶有一个顺时针流涡 ,阻碍了湾顶水与外海水的交换 ;夏季则为一个大的贴岸的顺时针流环 ,内嵌许多局地涡旋。这些与渤黄东海海洋水文图集中给出的多年观测的环流基本相同 ,同时也被水文要素分布及耐盐浮游动物的出现所佐证。风的季节变化决定了渤海大部分海区、特别是海峡附近环流的季节变化 ,但辽东湾东岸众多的岬角涡旋却不随季节变化 ,因为它们是由潮波系统与岬角岸型变化的非线性相互作用产生的。

关键词：环流输运季节变化渤海数值模拟风温度层结