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Preliminary comparison of trace metals in coastal aerosols between Qingdao and Liverpool

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Chinese Journal of Oceanology and Limnology 2008年第2期26卷 203-214页

作者：刘昌岭张经 Roy CHESTER Qingdao Institute of Marine Geology State Key Laboratory of Estuarine and Coastal Research East China Normal University oceanography laboratories Department of Earth Sciencethe University of LiverpoolBedford Street North

Aerosol samples were collected at two coastal suburban stations, Qingdao （China） in 1995-1996 and Liverpool （U.K.） in 1995, respectively. The samples were analyzed to determine the concentrations of trace metals （Cr, Zn, Cu, Co, Ni, Pb, V, and Cd） as well as A1, Fe and Mn. Data were examined to understand the difference of trace metals in aerosols between coastal zones downwind the developing area （near the Yellow Sea） and developed region （near the Irish Sea）. The results show that most elements at Qingdao have levels 4-5 times higher than those at Liverpool, particularly for the crust-dominated elements （e.g. Al, Fe and Mn）. Moreover, the aerosol composition at Qingdao is higher in spring than in summer, underlying the influence of westerlies and local emissions in combination, whereas seasonal change of aerosol composition is not significant at Liverpool. The enrichment factors for the crustal source elements （EFcrust） at Liverpool are much higher than those at Qingdao. The contributions from the pollutant source （Rp） for some trace metals like Cu, Pb, Zn and Cd are 〉90% at Qingdao and Liverpool, suggesting overwhelming anthropogenic contributions to these metals. The contributions from crustal source （Re） for trace metals tend to increase with higher aerosol levels and Al concentration at Qingdao, indicating a good correlation between the crust-dominated component and the air mass. At Liverpool, the Rc values for trace metals are positively correlated with Al concentrations instead of with aerosol mass, suggesting that Al in aerosols represents the crustal component even though the aerosols come from different sources.

关键词： aerosols trace metals Qingdao the Yellow Sea coast Liverpool the Irish Sea coast

Iron-handling solute carrier SLC22A17 as a blood-brain barrier target after stroke

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Neural Regeneration Research 2025年第11期20卷 3207-3208页

作者： Xueqi Ren Wenlu Li Key Laboratory of Neuropharmacology and Translational Medicine of Zhejiang Province School of Pharmaceutical SciencesZhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Neuroprotection Research laboratories Departments of Radiology and NeurologyMassachusetts General HospitalHarvard Medical SchoolBostonMAUSA

The pathophysiology of ischemic stroke is complex and multifactorial,involving various forms of cell death such as apoptosis,autophagy,and necrosis.A recent study suggests that oxidative and inflammatory stress can induce ferroptosis,a specialized form of cell death characterized by the accumulation of lipid peroxides dependent on intracellular iron overload(Li and Jia,2023).

关键词： death specialized barrier

Distribution Pattern of Photosynthetic Picoplankton and Heterotrophic Bacteria in the Northern South China Sea

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Journal of Integrative Plant Biology 2007年第3期49卷 282-298页

作者： Yu-Ming Cai Xiu-Ren Ning Cheng-Gang Liu Qiang Hao Ocean University of China Qingdao 266003 China State Oceanic Administration Key laboratories of Marine Ecosystem and Biogeochemistry Hangzhou 310012 China Second Institute of oceanography SOA Hangzhou 310012 China

The environmental regulation of plcoplankton distribution in the northern South China Sea was examined In winter and summer of 2004. The average abundance of Synechococcus, Prochlorococcus, and heterotrophlc bacteria was lower In winter （30, 21, and 780×10^3 cells/cm^3, respectively） than In summer （53, 85, and 1 090×10^3 cells/cm^3, respectively）, but the seasonal pattern was opposite for plcoeukaryotlc phytoplankton （4 500 and 3 200 cells/cm^3 In winter and summer, respectively）. Synechococcus, picoeukaryotes, and bacteria were most abundant in the nutrient-rich coastal zone and continental shelf, but Prochlorococcus was most abundant In the continental slope and open ocean. The vertical distribution of each photosynthetic group and heterotrophlc bacteria changed between the two seasons. Synechococcus populations with apparently different phycoerythrobilin content occurred at many stations In the summer. In addition, two different populations of Prochlorococcus were found：（i） small, weakly fluorescing cells in the surface layer; and （ii） larger, strongly fluorescent cells In the deep layer. The distribution pattern of photosynthetic plcoplankton and heterotrophlc bacteria depends on environmental effects and their ecophyslologlcal differences. The distribution of Synechococcus appeared to be related to nutrient availability, whereas the distribution of Prochlorococcus appeared to be limited by temperature. Synechococcus was the only plcophytoplankton with a consistent strong relationship with bacteria.

关键词： diel variation heterotrophic bacteria photosynthetic picoeukaryotes Prochlorococcus South China Sea spatial distribution structure standing stock Synechococcus

Development of high damage threshold laser-machined apodizers and gain filters for laser applications

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High Power Laser Science and Engineering 2016年第3期4卷 113-119页

作者： Patrick Rambo Jens Schwarz Mark Kimmel John L.Porter Sandia National laboratories

We have developed high damage threshold filters to modify the spatial profile of a high energy laser beam. The filters are formed by laser ablation of a transmissive window. The ablation sites constitute scattering centers which can be filtered in a subsequent spatial filter. By creating the filters in dielectric materials, we see an increased laser-induced damage threshold from previous filters created using ‘metal on glass' lithography.

关键词： apodization laser beam shaping laser micro-machining spatial filtering

An efficient method for unfolding kinetic pressure driven VISAR data

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High Power Laser Science and Engineering 2015年第3期3卷 50-58页

作者： M.Hess K.Peterson A.Harvey-Thompson Sandia National laboratories

Velocity Interferometer System for Any Reflector(VISAR) [Barker and Hollenbach, J. Appl. Phys. 43, 4669(1972)]is a well-known diagnostic that is employed on many shock physics and pulsed-power experiments. With the VISAR diagnostic, the velocity on the surface of any metal flyer can be found. For most experiments employing VISAR, either a kinetic pressure [Grady, Mech. Mater. 29, 181(1998)] or a magnetic pressure [Lemke et al., Intl J. Impact Eng. 38,480(2011)] drives the motion of the flyer. Moreover, reliable prediction of the time-dependent pressure is often a critical component to understanding the physics of these experiments. Although VISAR can provide a precise measurement of a flyer's surface velocity, the real challenge of this diagnostic implementation is using this velocity to unfold the timedependent pressure. The purpose of this paper is to elucidate a new method for quickly and reliably unfolding VISAR data.

关键词： laser driven blast wave pulsed-power VISAR

Recent laser upgrades at Sandia's Z-backlighter facility in order to accommodate new requirements for magnetized liner inertial fusion on the Z-machine

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High Power Laser Science and Engineering 2016年第4期4卷 1-12页

作者： Jens Schwarz Patrick Rambo Darrell Armstrong Marius Schollmeier Ian Smith Jonathan Shores Matthias Geissel Mark Kimmel John Porter Sandia National laboratories

The Z-backlighter laser facility primarily consists of two high energy, high-power laser systems. Z-Beamlet laser(ZBL)(Rambo et al., Appl. Opt. 44, 2421(2005)) is a multi-kJ-class, nanosecond laser operating at 1054 nm which is frequency doubled to 527 nm in order to provide x-ray backlighting of high energy density events on the Z-machine. Z-Petawatt(ZPW)(Schwarz et al., J. Phys.: Conf. Ser. 112, 032020(2008)) is a petawatt-class system operating at 1054 nm delivering up to 500 J in 500 fs for backlighting and various short-pulse laser experiments(see also Figure 10 for a facility overview). With the development of the magnetized liner inertial fusion(MagLIF) concept on the Z-machine, the primary backlighting missions of ZBL and ZPW have been adjusted accordingly. As a result, we have focused our recent efforts on increasing the output energy of ZBL from 2 to 4 kJ at 527 nm by modifying the fiber front end to now include extra bandwidth(for stimulated Brillouin scattering suppression). The MagLIF concept requires a well-defined/behaved beam for interaction with the pressurized fuel. Hence we have made great efforts to implement an adaptive optics system on ZBL and have explored the use of phase plates. We are also exploring concepts to use ZPW as a backlighter for ZBL driven MagLIF experiments. Alternatively, ZPW could be used as an additional fusion fuel pre-heater or as a temporally flexible high energy pre-pulse. All of these concepts require the ability to operate the ZPW in a nanosecond long-pulse mode, in which the beam can co-propagate with ZBL. Some of the proposed modifications are complete and most of them are well on their way.

关键词： adaptive optics high energy lasers MagLIF OPCPA petawatt lasers SBS suppression

Finescale Spiral Rainbands Modeled in a High-Resolution Simulation of Typhoon Rananim (2004)

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Advances in Atmospheric Sciences 2010年第3期27卷 685-704页

作者：李青青端义宏余晖傅刚 Shanghai Typhoon Institute Laboratory of Typhoon Forecast Technique/CMA National Meteorological Centre China Meteorological Administration laboratories of Ocean-Atmosphere Interaction and Climate and Physical oceanography Department of Marine MeteorologyOcean University of China

Finescale spiral rainbands associated with Typhoon Rananim （2004） with the band length ranging from 10 to nearly 100 km and band width varying from 5 to 15 km are simulated using the Fifth-Generation NCAR/Penn State Mesoscale Model （MM5）. The finescale rainbands have two types： one intersecting the eyewall and causing damaging wind streaks, and the other distributed azimuthally along the inner edge of the eyewall with a relatively short lifetime. The formation of the high-velocity wind streaks results from the interaction of the azimuthal flow with the banded vertical vorticity structure triggered by tilting of the horizontal vorticity. The vertical advection of azimuthal momentum also leads to acceleration of tangential flow at a relatively high Mtitude. The evolution and structures of the bands are also examined in this study. Further investigation suggests that the boundary inflection points are related tightly to the development of the finescale rainbands, consistent with previous findings using simple symmetric models. In particular; the presence of the level of inflow reversal in the boundary layer is a crucial factor controlling the formation of these bands. The near-surface wavy peaks of vertical vorticity always follow the inflection points in radial flow. The mesoscale vortices and associated convective updrafts in the eyewall are considered to strengthen the activity of finescale bands, and the updrafts can trigger the formation of the bands as they reside in the environment with inflow reversal in the boundary layer.

关键词： finescale rainbands dynamic and thermodynamic structure boundary layer instabilities Typhoon Rananim

CORRUGATED CIRCULAR WAVEGUIDE WITH DUAL-DEPTH CORRUGATIONS

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Science China Mathematics 1985年第10期28卷 1098-1114页

作者：杨可忠章日荣王汉礼 Shijiazhuang Communications laboratories

The propagation equation for corrugated circular waveguides with dual-depth corrugations derived by using space harmonics technique involves as many slot modes as possible. An analysis has also made for the influence of space harmonies and slot modes on the propagation constant, the hybrid factor and the radiation characteristics. Furthermore, an investigation has been presented for the effect on the propagation and radiation properties of the slot-depth ratio and other geometric parameters. The curves and conclusions made in this paper may be helpful for designing this kind of feed.

关键词： mode HE CORRUGATED CIRCULAR WAVEGUIDE WITH DUAL-DEPTH CORRUGATIONS

DUAL-SHAPED OFFSET REFLECTOR ANTENNAS WITH CIRCULAR APERTURE FOR REALIZING LOW CROSSPOLARIZATION

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Science in China,Ser.A 1986年第6期29卷 662-672页

作者：章日荣王汉礼杨可忠 Shijiazhuang Communication laboratories

An expression of aperture field crosspolarization has been derived in this paper for dual shaped offset reflector antennas, the first-order partial differential equation has also been presented for mapping function. The problem of making a search for the mapping function can be simplified as to solve a constant differential equation in terms of an iterative process. The geometric parameters meeting the given requirements and the mapping function can be determined rapidly by making use of these equations without repeatedly solving the second-order partial differential equation or a set of the first-order differential equations and doing complicated calculations for reconstructing the main reflector.

关键词： Th DUAL-SHAPED OFFSET REFLECTOR ANTENNAS WITH CIRCULAR APERTURE FOR REALIZING LOW CROSSPOLARIZATION