检索结果-南通市图书馆

Retrievals of atmospheric boundary layer temperature and moisture profiles by using Atmospheric Emitted Radiance Interferometer(AERI) measurements in Shouxian

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chinese Science Bulletin 2014年第8期59卷 795-801页

作者： Linjun Pan Daren L Key Laboratory for Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences

The ground-based Atmospheric Emitted Radiance Interferometer(AERI)was deployed in Shouxian,China in 2008 to measure down-welling infrared radiances with high *** on AERI observations,we propose a new method for retrieving vertical temperature and water vapor profiles in the planetary boundary layer(PBL).The method exclusively uses NCEP-2,a global reanalysis data as a first-guess profile in an iterative recursive *** PBL profiles of temperature and moisture under clear sky conditions in Shouxian have been retrieved using this new *** with coincident radiosonde measurements,we find that AERI is able to obtain more accurate temperature and water vapor profiles in the *** retrieval results with high temporal resolution can be used to monitor the PBL stability and evolution.

关键词：测量数据检索结果大气发射湿度廓线干涉仪大气边界层温度寿县

Marine dispersion of Fukushima-derived radiocesium in the North Pacific and its implications

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Science China Earth sciences 2025年

作者： Tong ZHANG Xiaolin HOU Yukun FAN State Key Laboratory of Loess and Quaternary Geology Shaanxi Key Laboratory of Accelerator Mass Spectrometry Technology and Application Xi'an AMS Center Institute of Earth Environment Chinese Academy of Sciences University of chinese academy of sciences Xi'an Institute for Innovative Earth Environment Research

A key scientific approach to addressing the environmental radiation risks from Fukushima nuclear contaminated water （FNCW） discharge into the ocean is understanding and predicting the marine dispersion of *** dispersion of radiocesium (CsF:134Cs,137Cs) from the Fukushima nuclear accident in the North Pacific and its marginal seas post-2011 was systematically summarized,focusing on pathways,vertical distribution changes,and transit *** research examined CsFdispersion through the Kuroshio Extension and denser central mode water （D-CMW） to the eastern North Pacific,as well as through subtropical mode water （STMW）,lighter central mode water （L-CMW）,and D-CMW to the subtropical western North Pacific,China Seas,and Sea of *** considered broader implications of CsFdispersion in light of ongoing FNCW *** this prolonged liquid discharge and Kuroshio Extension’s barrier effect,it is crucial to emphasize the role of CMW besides STMW in transporting FNCW to the subtropical western North Pacific and its marginal *** research should focus on the key mechanism and longitude range of CMW crossing the Kuroshio *** short-lived134Cs decays rapidly during the storage and dispersion of FNCW,long-lived135Cs and135Cs/137Cs ratios can serve as valuable tracers for detecting and quantifying ***,there is an urgent need for high-precision analysis of these key radionuclides and their characteristic *** promptly detect,assess,and respond to FNCW intrusion,continuous monitoring and identification of nuclear pollution sources in key ocean currents and straits are ***,interdisciplinary research integrating monitoring with marginal sea circulation dynamics and high-resolution numerical simulations should be a priority

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A monolithic 60GHz balanced low noise amplifier

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Journal of Semiconductors 2015年第4期36卷 110-114页

作者：杨雪杨浩张海英郑新年戴志伟李志强杜泽保 Institute of Microelectronics Chinese Academy of Sciences

This paper presents a 60 GHz balanced low noise amplifier. Compared with single-ended structures, the balanced structure can obtain a better input/output return loss, a lower noise figure （NF）, a 3 dB improvement of the 1 dB compression point, a 6 dB improvement of 1M3 and a doubled dynamic range. Each single-ended amplifier in this paper uses a four-stage cascade structure to achieve a high gain in broadband. At the operating frequency range of 59-64 GHz, the small signal gain of the balanced amplifier is more than 20 dB. Both the input and output return losses are less than -12 dB. The output 1 dB compression power is 10.5 dBm at 60 GHz. The simulation result for the NF is better than 3.9 dB. The chip is fabricated using a 0.15 μm GaAs pHEMT process with a size of 2.25 × 1.7 mm2.

关键词： balanced amplifier 60 GHz low noise

Shielding of the geomagnetic field reduces hydrogen peroxide production in human neuroblastoma cell and inhibits the activity of CuZn superoxide dismutase

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Protein & Cell 2017年第7期8卷 527-537页

作者： Hai-tao Zhang Zi-jian Zhang Wei-chuan Mo Ping-dong Hu Hai-min Ding Ying Liu Qian Hua Rong-qiao He State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China University of chinese academy of sciences Beijing 100049 China Institute of Beijing chinese Traditional Medicine Beijing University of Chinese Medicine Beijing 100029 China CAS KeY Laboratory of Mental Health Institute of Psychology Beijing 100101 China

Accumulative evidence has shown the adverse effects of a geomagnetic field shielded condition, so called a hypomagnetic field （HMF）, on the metabolic processes and oxidative stress in animals and cells. However, the underlying mechanism remains unclear. In this study, we evaluate the role of HMF on the regulation of cellular reactive oxygen species （ROS） in human neuroblastoma SH-SY5Y cells. We found that HMF exposure led to ROS decrease, and that restoring the decrease by additional H2O2 rescued the HMF-enhanced cell proliferation. The measurements on ROS related indexes, including total anti-oxidant capacity, H2O2 and superoxide anion levels, and superoxide dismutase （SOD） activity and expres- sion, indicated that the HMF reduced H2O2 production and inhibited the activity of CuZn-SOD. Moreover, the HMF accelerated the denaturation of CuZn-SOD as well as enhanced aggregation of CuZn-SOD protein, in vitro. Our findings indicate that CuZn-SOD is able to response to the HMF stress and suggest it a mediator of the HMF effect.

关键词： hypomagnetic field reactive oxygenspecies hydrogen peroxide superoxide dismutase,oxidative stress

Elimination of the geomagnetic field stimulates the proliferation of mouse neural progenitor and stem cells

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Protein & Cell 2016年第9期7卷 624-637页

作者： Jing-Peng Fu Wei-Chuan Mo Ying Liu Perry F. Bartlett Rong-Qiao He State Key Laboratory of Brain and Cognitive Science Institute of Biophysics Chinese Academy of Sciences Beijing 100101 China Queensland Brain Institute University of Queensland Brisbane QLD 4072 Australia University of the chinese academy of sciences Beijing 100049 China Alzheimer's Disease Center Beijing Institute for Brain Disorders Capital Medical University Beijing 100069 China

Living organisms are exposed to the geomagnetic field （GMF） throughout their lifespan. Elimination of the GMF, resulting in a hypogeomagnetic field （HMF）, leads to central nervous system dysfunction and abnormal development in animals. However, the cellular mecha-nisms underlying these effects have not been identified so far. Here, we show that exposure to an HMF （〈200 nT）, produced by a magnetic field shielding chamber, pro- motes the proliferation of neural progenitor/stem cells （NPCslNSCs） from C57BL/6 mice. Following seven-day HMF-exposure, the primary neurospheres （NSs） were significantly larger in size, and twice more NPCslNSCs were harvested from neonatal NSs, when compared to the GMF controls. The self-renewal capacity and multi- potency of the NSs were maintalned, as HMF-exposed NSs were posltlve for NSC markers （Nestin and Sox2）, and could differentiate into neurons and astrocytelglial cells and be passaged continuously. In addition, adult mice exposed to the HMF for one month were observed to have a greater number of proliferative cells In the subventrlcular zone. These flndlngs indicate that continuous HMF-exposure increases the proliferation of NPCslNSCs, In vitro and in vlvo. HMF-dlsturbed NPCs/NSCs production probably affects brain development and function, which provides a novel clue for elucidating the cellular mechanisms of the *** response.

关键词： hypomagnetic field neural progenitor/stemcells neurosphere proliferation sternness multipotency

Recognizing the orbital angular momentum(OAM)of vortex beams from speckle patterns

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Science China(Physics,Mechanics & Astronomy) 2022年第4期65卷 55-61页

作者： Zhiyuan Wang Xuetian Lai Huiling Huang Xiaoyan Wang Haoran Li Ziyang Chen Jun Han Jixiong Pu Fujian Key Laboratory of Light Propagation and Transformation College of Information Science and EngineeringHuaqiao UniversityXiamen 361021China Quanzhou Institute of Equipment Manufacturing Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesQuanzhou 362000China

The orbital angular momentum(OAM)of vortex beams offers a new degree for information encoding,which has been applied to optical *** measurement is essential for these applications,and has been realized in free space by several ***,these methods are inapplicable to estimate the OAM of vortex beams directly from the speckle patterns in the exit end of a multimode fiber(MMF).To tackle this issue,we design a convolutional neural network(CNN)to realize 100%accuracy recognition of two orthogonally polarized OAM modes from speckle ***,we demonstrate that even when the speckle patterns are cropped to only 1/64 of the original patterns,the recognition accuracy of the designed neural network is still higher than 98%.We also study the recognition accuracy of cropped speckles in different areas of speckle patterns to verify the feasibility of OAM recognition after *** results demonstrate that recognizing the OAMs of two orthogonally polarized vortex beams from only a portion of speckle patterns in the exit end of an MMF is feasible,offering the potential to construct a 1×N data transmission scheme.

关键词： optical angular momentum speckle pattern orthogonal polarization fiber optical communication deep learning

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Projection of Landslides in China during the 21st Century under the RCP8.5 Scenario

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Journal of Meteorological Research 2019年第1期33卷 138-148页

作者： Shuangshuang HE Jun WANG Huijun WANG Nansen–Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences University of chinese academy of sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science &Technology Key Laboratory of Meteorological Disaster Nanjing University of Information Science & Technology

More and more rainstorms and other extreme weather events occur in the context of global warming, which may increase the risks of landslides. In this paper, changes of landslides in the 21 st century of China under the high emission scenario RCP8.5(Representative Concentration Pathway) are projected by using a statistical landslide forecasting model and the regional climate model RegCM4.0. The statistical landslide model is based on an improved landslide susceptibility map of China and a rainfall intensity–duration threshold. First, it is driven by observed rainfall and RegCM4.0 rainfall in 1980–99, and it can reproduce the spatial distribution of landslides in China pretty ***, it is used to forecast the landslide changes over China in the future under the RCP8.5 scenario. The results consistently reveal that landslides will increase significantly in most areas of China, especially in the southeastern, northeastern, and western parts of Northwest China. The change pattern at the end of the 21 st century is generally consistent with that in the middle of the 21 st century, but with larger increment and magnitude. In terms of the probability,the proportion of grid points that are very likely and extremely likely to experience landslides will also increase.

关键词： landslides projection statistical landslide forecasting model regional climate model

An L-band HTS duplexer with improved performance

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chinese Science Bulletin 2010年第31期55卷 3527-3532页

作者： Jia Wang Qiang Zhang Bin Cui Jin Guo YongBo Bian XiaoFeng He ChunGuang Li XueQiang Zhang Hong Li WuXia Li et al. chinese Acad Sci Inst Phys Beijing 100190 Peoples R China

An L-band HTS duplexer with improved performance for communication applications has been *** is an improved version of the duplexer previously developed by our *** duplexer was composed of a T-junction and two *** channel has a 10-pole quasi-elliptic function bandpass HTS filter with a bandwidth of 27 MHz,and center frequencies at 1200 MHz and 1260 *** achieve higher performance,especially a good balance between selectivity and flat group delay,the two pairs of transmission zeros from the two filters were reassigned so that one pair is used for high selectivity and the other for flat group *** reduce the influence of parasitical coupling,new coupling structures were developed in the simulation *** duplexer was fabricated on a 2 inch diameter,0.5 mm thick LaAlO3 wafer with a double-sided YBCO *** measured results showed a very high performance:a mid-band insertion loss of 0.2 dB,a return loss better than-14 dB,a shape factor better than 1.4:1,an out-of-band rejection of better than 70 dB in a wide frequency range up to 3 GHz and excellent isolation(higher than 80 dB) between the two *** addition,the frequency band 5 ns group delay variation is over 10.5 MHz(38.7% of 1 dB bandwidth).

关键词：双面打印高温超导 L波段性能带宽滤波器插入损耗通信应用丁字路口

Landslide susceptibility assessment of the region affected by the 25 April 2015 Gorkha earthquake of Nepal

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Journal of Mountain Science 2016年第11期13卷 1941-1957页

作者： Amar Deep Regmi Megh Raj Dhital ZHANG Jian-qiang SU Li-jun CHEN Xiao-qing Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentCASChengdu 610041China Central Department of Geology Tribhuvan UniversityKirtipur 44613Nepal

Nepal was hit by a 7.8 magnitude earthquake on 25^(th) April,*** main shock and many large aftershocks generated a large number of coseismic landslips in central *** have developed a landslide susceptibility map of the affected region based on the coseismic landslides collected from remotely sensed data and fieldwork,using bivariate statistical model with different landslide causative *** the investigation,it is observed that most of the coseismic landslides are independent of previous *** of 3,716 mapped landslides,we used 80% of them to develop a susceptibility map and the remaining 20% were taken for validating the model.A total of 11 different landslide-influencing parameters were *** include slope gradient,slope aspect,plan curvature,elevation,relative relief,Peak Ground Acceleration(PGA),distance from epicenters of the mainshock and major aftershocks,lithology,distance of the landslide from the fault,fold,and drainage *** success rate of 87.66% and the prediction rate of86.87% indicate that the model is in good agreement between the developed susceptibility map and theexisting landslides ***,lithology,slope angle and elevation have played a major role in triggering the coseismic mass *** susceptibility map can be used for relocating the people in the affected regions as well as for future land development.

关键词： Earthquake Himalaya Coseismic landslide Susceptibility bivariate statistical model Nepal