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High Voltage 2024年第3期9卷 674-684页

作者： Kerstin Friebe frank Jenau TU Dortmund University Institute of High Voltage EngineeringDortmundGermany

Partial discharge diagnosis is an important part of monitoring and diagnosing compo-nents of the power transmission *** different patch antenna structures for the detection of partial discharges are *** patch antennas,which are realisable in a variety of geometric structures,are already the subject of *** offer the advantage of contactless detection without intervention in the test object or the measuring circuit,and also offer the possibility of alignment independent detection compared to directional ***,it is important and required to examine different structures extensively at the same measurement setup and to compare their *** achieve this,four different configurations of patch antenna structures based on basic geometries all in antipodal design are realised:a logarithmic periodic structure,a Hilbert fractal structure and two tapered slot *** are exposed to the same conditions on a special and unique measurement *** the main aspect,the performance of orientation independent detection of partial discharges patch antennas with varying distance and rotation in relation to the partial discharge source as well as the operating bandwidth is *** rate the structures,an evaluation scheme is created and a sensitivity matrix is generated.

关键词： antenna patch structures

Numerical and experimental investigation of sloshing under large amplitude roll excitation

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Journal of Hydrodynamics 2021年第4期33卷 787-803页

作者： Ronja Hoch frank-Hendrik Wurm Institute of Turbomachinery University of RostockRostockGermany

To enable a virtual design and optimization process of partially filled coolant tanks a reliable numerical approach is needed to predict the liquid and gas two phase flow inside the *** this study numerical results are validated by experimental data to examine the suitability of the method for the tank design *** liquid motion inside the tanks can be described as sloshing with high amplitude,off-resonant roll excitation and was examined using a homogeneous multiphase model and VOF interface capturing approach as well as an experimental setup including piezoelectric pressure sensors and qualitative observation of the free *** effect of two vertical baffles on the maximum pressure and the position of phase interface was *** comparison between the computational and experimental results reveals that the numerical model tends to under predict the experimental peak pressures but resolves the liquid surface in close agreement with the experiments.

关键词： Multiphase flows sloshing unsteady Reynolds averaged Navier-Stokes(URANS)

Comparing the Upper Triassic Deep-sea Flysch of the Shannan Terrane with the Coeval Shallow Shelf Sediments of the Tethys Himalaya,Southern Tibet

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Acta Geologica Sinica(English Edition) 2021年第2期95卷 348-354页

作者： LI Xianghui frank MATTERN School of Earth Sciences and Engineering Nanjing UniversityNanjing 210023China College of Science Earth Science DepartmentSultan Qaboos UniversityAl-KhodPO Box 36Sultanate of Oman

The provenance and paleogeography of the Upper Triassic deep-sea flysch Langjiexue Group(LG)of the Shannan Terrane in the northeastern Himalaya orogen,south of Yarlung Zangbo,have been disputed in recent years since its affinity to the Tethys Himalaya was suspected during the early 2000 *** on the earlier discoveries of the Upper Permian–Triassic basalts and mafic dykes from the LG and of coeval detrital zircons from the Qulonggongba Formation(QF)in shallow shelf sediments of the Tethys Himalaya,the previous viewpoints on the basin and tectonics of the LG have been recently *** compared the two units of the Upper Triassic,and our results reveal a number of differences,discrepancies,and inconsistencies in the debate,raising crucial questions on the postulation and provenance model of the remote Gondwanide Orogen for the *** is suggested that more observations and evidence are needed to further improve the paleogeographic understanding and relationship of the two units.

关键词： sedimentology paleogeography flysch shelf sediment Late Triassic Shannan Terrane Tethys Tibet

Endoscopic ultrasonography-guided drainage for patients with symptomatic obstruction and enlargement of the pancreatic duct

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World Journal of Gastroenterology 2015年第46期21卷 13140-13151页

作者： Uwe Will Andreas Reichel frank Fueldner frank Meyer Department of Internal Medicine Ⅲ (Gastroenterology and Hepatology) Municipal Hospital (SRH Waldklinikum Gmb H) Department of General Abdominal and Vascular SurgeryUniversity Hospital

AIM: To evaluate the use of translumenal pancreatography with placement of endoscopic ultrasonography(EUS)-guided drainage of the pancreatic ***: This study enrolled all consecutive patients between June 2002 and April 2014 who underwent EUSguided pancreatography and subsequent placement of a drain and had symptomatic retention of fluid in the pancreatic duct after one or more previous unsuccessful attempts at endoscopic retrograde cannulation of the pancreatic duct. In all,94 patients underwent 111 interventions with one of three different approaches:(1) EUS-endoscopic retrograde drainage with a rendezvous technique;(2) EUS-guided drainage of the pancreatic duct; and(3) EUS-guided,internal,antegrade drainage of the pancreatic ***: The mean duration of the interventions was 21 min(range,15-69 min). Mean patient age was 54 years(range,28-87 years); the M:F sex ratio was 60:34. The technical success rate was 100%,achieving puncture of the pancreatic duct including pancreatography in 94/94 patients. In patients requiring drainage,initial placement of a drain wassuccessful in 47/83 patients(56.6%). Of these,26 patients underwent transgastric/transbulbar positioning of a stent for retrograde drainage; plastic prostheses were used in 11 and metal stents in 12. A ring drain(antegrade internal drainage) was placed in three of these 26 patients because of anastomotic stenosis after a previous surgical intervention. The remaining 21 patients with successful drain placement had transpapillary drains using the rendezvous technique; the majority(n = 19) received plastic prostheses,and only two received metal stents(covered self-expanding metal stents). The median follow-up time in the 21 patients with transpapillary drainage was 28 mo(range,1-79 mo),while that of the 26 patients with successful transgastric/transduodenal drainage was 9.5 mo(range,1-82 mo). Clinical success,as indicated by reduced or absence of further pain after the EUS-guided intervention was

关键词： Endoscopic ultrasonography Endoscopic ultrasonogra

Efficacy of chlorfenapyr against adult Tribolium castaneum exposed on concrete＂ effects of exposure interval, concentration and the presence of a food source after exposure

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Insect Science 2009年第2期16卷 157-163页

作者： frank H. Arthur USDA-ARS Grain Marketing and Production Research Center Manhattan Kansas USA

Chlorfenapyr, an insecticidal pyrrole, was applied to concrete arenas at concentrations of 1. 1, 0.825, 0.55, and 0.275 g of active ingredient [AI]/m^2. Adult Tribolium castaneum （Herbst）, the red flour beetle, were exposed for 2, 4, or 8 h at each concentration, then removed and held either with or without food （wheat flour） for 7 days. Survival was assessed when the beetles were removed fi＇om the exposure arenas and daily during the post- exposure period. In the presence of food, survival was high regardless of concentration and the day on which post-treatment survival was assessed, but survival did decrease as the exposure period increased from 4 to 8 h. When the beetles were not given food after exposure, survival at each concentration and exposure period declined during the 1-week post- exposure assessments. This pattern of decrease could be described by linear and non-linear equations. Results show the presence of food material greatly compromised effectiveness of the insecticide, and emphasize the importance of cleaning and sanitation in conjunction with insecticide treatments.

关键词： chlorfenapyr efficacy sanitation Tribolium castaneum

Effect of hot rolling on microstructure and properties of the ZEK100 alloy

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Journal of Magnesium and Alloys 2019年第1期7卷 27-37页

作者： Amjad Javaid frank Czerwinski CanmetMATERIALS 183 Longwood Road SouthHamiltonOntario L8P 0A5Canada

Attempts to expand manufacturing capabilities of magnesium-based sheet materials are *** as-cast ZEK100(Mg-1.2Zn-0.35Zr-0.17Nd,in wt%)magnesium alloy was subjected to hot rolling at temperatures from 350℃to 450℃using the laboratory 50 ton reversible mill with preheated rolls to manufacture the 1.5-1.7 mm thick *** rolling temperature affected the sheet properties and an increase in the rolling temperature from 250 to 450℃caused reduction of tensile strength from 257 to 228 MPa ac-companied by a reduction in tensile yield stress from 237 to 185 *** the same time,the alloy elongation increased from 17 to 21%.For the same rolling temperature range,the compressive strength reduced from 418 to 351 *** post-rolling annealing at 450℃led to reduction of both tensile and compressive properties with the largest changes corresponding to the rolling temperature of 350°*** correlation between the alloy grain size after rolling and the sheet properties was established where a reduction in grain size was accompanied by an increase of both the tensile/compressive strength and yield *** on Hall-Petch relationship and an average grain size the correlation developed in this study may be used as the prediction model for properties of the hot rolled magnesium *** results are discussed in terms of recent developments in magnesium sheet alloys and the vital role played in this process by rare earth elements.

关键词： Magnesium alloys Hot deformation Microstructure Rare earths Sheet rolling

Flow frictional characteristics of microencapsulated phase change material suspensions flowing through rectangular minichannels

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Science China(Technological Sciences) 2006年第4期49卷 445-456页

作者： frank Dammel Peter Stephan Chair of Technical Thermodynamics Darmstadt University of Technology Germany

An experimental investigation was conducted on the laminar flow frictional characteristics of suspensions with microencapsulated phase change material (MEPCM) in water flowing through rectangular copper minichannels. The MEPCM was provided at an average particle size of 4.97 μm, and was mixed with distilled water to form suspen- sions with various mass concentrations ranging from 0 to 20%. The experiment was per- formed to explore the effect of MEPCM mass concentration on friction factor and pressure drop in the minichannels. The Reynolds number ranged from 200 to 2000 to provide laminar and transitional flows. It was found that the experimental data for the suspensions with 0 and 5% concentration agree well with the existing theoretical data for an incom- pressible, fully developed, laminar Newtonian flow. For the suspensions with mass con- centrations higher than 10%, there is an obvious increase in friction factor and pressure drop in comparison with laminar Newtonian flow.

关键词： microencapsulated phase change material suspension, friction factor, rectangular minichannel.

Aerosol distribution and efficacy in a commercial food warehouse

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Insect Science 2008年第2期15卷 133-140页

作者： frank H. Arthur USDA-ARS Grain Marketing and Production Research Center Manhattan Kansas USA

A series of field trials were conducted in a commercial food storage facility to evaluate exposure of stored-product insects to aerosol formulations of synergized pyrethrins and the insect growth regulator methoprene. When adults of Tribolium castaneum （Herbst）, the red flour beetle, and Tribolium confusum （Jacqueline DuVal）, the confused flour beetle were exposed with and without a food source to synergized pyrethrin aerosol, there was no difference in adult mortality with respect to availability of food at either 7 or 14 days after exposure （P≥0.05）. However, mortality was lower in T. confusum （40.4% and 79.3% with flour at 7 and 14 days, 38.9% and 84.8% without flour at 7 and 14 days） compared to T. castaneum （96.5% and 99.8% with flour at 7 and 14 days, 91.0% and 98.7% without flour at 7 and 14 days）. Few late-stage larvae and pupae of either species exposed to the pyrethrin aerosol emerged as adults. In tests with methoprene aerosol, adult emergence of exposed 3- and 4-week-old larvae of T. confusum was less than 2%. Only 0.3% of 4-week-old larvae of T. castaneum exposed in open and obstructed areas emerged as adults. Emergence of adults from eggs of Plodia interpunctella （Hubner）, the Indianmeal moth, embedded in culture media and exposed to the methoprene aerosol was 13.2%±3.5%. Results show that the aerosols evaluated in our study could give effective control of some of the major storedproduct insect pests in commercial food storage facilities, and may offer an alternative to fumigation.

关键词： aerosols control methoprene Plodia pyrethrin Tribolium

Antiviral factors and their counteraction by HIV-1: many uncovered and more to be discovered

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Journal of Molecular Cell Biology 2024年第2期16卷 1-10页

作者： Dorota Kmiec frank Kirchhoff Institute of Molecular Virology Ulm University Medical Center89081 UlmGermany

Extensive studies on HIV-1 have led to the discovery of a variety of structurally and functionally diverse innate defense factors that target various steps of the retroviral replication *** of them,such as APOBEC3,tetherin,and SERINC5,are well *** importance is evident from the fact that HIV-1 uses its accessory proteins Vif,Vpu,and Nef to counteract ***,the list of antiviral factors is constantly increasing,and accumulating evidence suggests that innate defense mechanisms,which restrict HIV-1 and/or are counteracted by viral proteins,remain to be *** antiviral factors are relevant to diseases other than HIV/AIDS,since they are commonly active against various viral *** this review,we provide an overview of recently reported antiretroviral factors and viral countermeasures,present the evidence suggesting that more innate defense mechanisms remain to be discovered,and discuss why this is a challenging but rewarding task.

关键词： HIV-1 restriction factors viral antagonists interferon-stimulated genes antiviral factors

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TeV astronomy

Frontiers of physics 2013年第6期8卷 714-747页

作者： frank M. Rieger Max-Planck-Institut fiir Kernphysik P.O. Box 103980 69029 Heidelberg Germany Institut de Ciencies de L'Espai (IEEC-CSIC) Campus UAB Torte C5 08193 Bellaterra Spain Dublin Institute for Advanced Studies 31 Fitzwilliam Place Dublin 2 Ireland European Associated Laboratory for Gamma-Ray Astronomy jointly supported by CNRS and MPG

With the successful realization of the current-generation of ground-based detectors, TeV Astronomy has entered into a new era. We review recent advances in VHE astronomy, focusing on the potential of Imaging Atmospheric Cherenkov Telescopes （IACTs）, and highlight astrophysical implications of the results obtained within recent years.

关键词： TeV astronomy gamma-rays Cherenkov telescopes high-energy astrophysics