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Nonlocal Symmetries of the Camassa-Holm Type Equations

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Chinese Annals of Mathematics,Series B 2020年第3期41卷 407-418页

作者： Lu ZHAO Changzheng QU center for Nonlinear studies and Department of Mathematics Ningbo UniversityNingbo 315211ZhejiangChina

A class of nonlocal symmetries of the Camassa-Holm type equations with bi-Hamiltonian structures, including the Camassa-Holm equation, the modified Camassa-Holm equation, Novikov equation and Degasperis-Procesi equation, is studied. The nonlocal symmetries are derived by looking for the kernels of the recursion operators and their inverse operators of these equations. To find the kernels of the recursion operators, the authors adapt the known factorization results for the recursion operators of the KdV, modified KdV, Sawada-Kotera and Kaup-Kupershmidt hierarchies, and the explicit Liouville correspondences between the KdV and Camassa-Holm hierarchies, the modified KdV and modified Camassa-Holm hierarchies, the Novikov and Sawada-Kotera hierarchies, as well as the Degasperis-Procesi and Kaup-Kupershmidt hierarchies.

关键词： Nonlocal symmetry Recursion operator Camassa-Holm equation Modified Camassa-Holm equation Novikov equation Degasperis-Procesi equation Liouville correspondence

Iodine-mediated facile dehydrogenation of dihydropyridazin-3(2H)one

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Chinese Chemical Letters 2011年第12期22卷 1435-1438页

作者： Vivek T.Humne Shankaraiah G.Konda Kamal Hasanzadeh Pradeep D.Lokhande center for Advance studies Department of ChemistryUniversity of PunePune 411007India

A new protocol for the dehydrogenation of dihydropyridazin-3（2H）-one has been carried out by catalytic amount of iodine in dimethyl sulphoxide in good yield with easy workup.

关键词： Dehydrogenation Iodine Dihydropyridazin-3(2H)-one Pyridazin-3(2H)-one

An Index of East Asian Winter Monsoon Applied to the Description of China's Mainland Winter Temperature Changes

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Acta meteorologica Sinica 2008年第4期22卷 522-529页

作者：朱艳峰 Laboratory for Climate studies of China Meteorological Administration National Climate Center

Using the NCEP/NCAR reanalysis data （Version 1.0） and the observation data of China from January 1951 to February 2007, a new index of East Asian winter monsoon circulation （I EAWM） was defined based on the comparison of previous different winter monsoon indices and circulation factors influencing the winter climate over China. Its relationships with winter temperature over China and large-scale circulation were analyzed. Results show that IEAWM can successfully describe the variation of China＇s mainland winter temperature and the East Asian winter monsoon （EAWM） system. This index reflects the integrated effect of the circulations over high and low latitudes and the thermal difference between the continent and the ocean. While in the previous studies, most monsoon indices only describe the single monsoon member. The IEAWM is a good indicator of the intensity of the EAWM. Positive values of/EAWM correspond to the strong EAWM, the stronger Siberian high and East Asian trough than normal , and the strengthening of the meridional shear of 500-hPa zonal wind between high and low latitudes over East Asia, and therefore, the southward cold advection becomes stronger and leads to the decrease in surface temperature over China; and vice versa. The IEAWM inter decadal change is obviously positive before the mid-1980s, but negative since the mid-1980s, in good agreement with the fact of the winter warming in China after 1985.

关键词： index of East Asian winter monsoon China's mainland winter temperature changes

Evaluating the accuracy of two satellite-based Quantitative Precipitation Estimation products and their application for meteorological drought monitoring over the Lake Victoria Basin,East Africa

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Geo-Spatial Information Science 2022年第3期25卷 500-518页

作者： Priyanko Das Zhenke Zhang Hang Ren center of African studies Nanjing UniversityNanjingChina and School of Geographic and Oceanographic SciencesNanjing UniversityNanjingChina center of African studies Nanjing UniversityNanjingChina and School of Geographic and Oceanographic SciencesNanjing University Nanjing China Institute of Population studies Nanjing University of Posts and TelecommunicationsNanjingJiangsu provinceChina

This study evaluates the high-resolution satellite estimated long-term precipitation data for monitor-ing the drought condition over the Lake Victoria Basin(LVB)from 1984 to *** Precipitation Indices(SPI)were used to capture the short,medium and long-term meteorological drought conditions at multiple time scales(i.e.3,6,and 12).For these,the following two primaries Quantitative Precipitation Estimation(QPEs)products were employed-1)Climate Hazards group Infra-Red Precipitation with Station(CHIRPS),and 2)the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Network-Climate Data Record(PERSIANN-CDR).This dataset was compared based on the observation data obtained from the Climate Research Unit(CRU)over the nine selected regions surrounding lake *** performance of these two QPEs products was evaluated using seven statistical *** findings of this study indicate that the CHIRPS and PERSIANN-CDR datasets could capture the behavior of drought magnitude based on the time scale of SPI-3,SPI-6,*** results indicate that 2012 and 2017 are significant severe drought years in the recent decade over ***,the CHIRPS datasets provide good agreement(Correlation Coefficient(CC)=0.65)with observation,whereas PERSIANN-CDR present satisfactory results(CC=0.54).In addition,Hurst(H)exponent was used to predict the future drought trend and found that the CHIRPS performed well to predict the degree of drought ***,this study considers the CHIRPS product for near-real-time drought monitoring and PERSIANN-CDR for historical drought ***,the outcome from the H values is greater than 0.5,which indicates the future drought trend would be decreased over *** results are useful for developing the strategies for drought hazards and water resource management in LVB.

关键词： CHIRPS CRU hurst exponent PERSIANN-CDR SPI

Boreal Summer Intraseasonal Oscillation and Its Possible Impact on Precipitation over Southern China in 2019

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Journal of Meteorological Research 2021年第4期35卷 571-582页

作者： Jieli HONG Zongjian KE Yuan YUAN Xie SHAO Laboratory for Climate studies National Climate CenterChina Meteorological AdministrationBeijing 100081

Based on daily precipitation observation data in China,the intraseasonal oscillation(ISO)features of summer precipitation over southern China in 2019 have been investigated by wavelet and band-pass filtering *** results show that enhanced(suppressed)precipitation occurred over southern China during early(late)boreal *** signals of both 10-20-and 30-60-day ISO in southern China are remarkable,with the amplitude of the10-20-day ISO larger than the 30-60-day ISO in boreal summer *** synergistic effect of the 10-20-and 30-60-day ISO wet phases was found to exert a tremendous influence on persistent heavy precipitation in July 2019,when the amount of precipitation reached its maximum in southern China since *** atmospheric circulation and convection evolution characteristics of both 10-20-and 30-60-day ISO are further *** anomalous low-level anticyclone over the South China Sea is prominently linked to the wet phase of the 10-20-day ISO,whereas an anomalous low-level cyclone over southern China is dominantly associated with the wet phase of the 30-60-day *** events enhance the water vapor convergence and ascending motion over southern ***,the atmospheric circulation that accompanied the synergism of the wet phases of the 10-20-and 30-60-day ISO resulted in persistent heavy precipitation over southern China in July 2019.

关键词： heavy precipitation intraseasonal oscillation(ISO) southern China

Uranium enrichment determination by high-energy photon interrogation

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 2000-2004页

作者： ZHU JianYu ZHANG SongBai WU Jun center for Strategic studies China Academy of Engineering Physics Beijing 100088 China

Uranium enrichment determination by non-destructive assay is an important method in authenticating the nuclear warhead or uranium component in deep nuclear reduction *** this paper,the feasibility of applying the high-energy photon interrogation to determine the uranium enrichment is *** models are presented which were simulated by particle Monte Carlo transport *** results indicate that the relation curves of the released neutrons and the enrichment of uranium objects are almost *** a uranium object of a given shape,the uranium enrichment can be obtained with the relation curves,which could be got in advance by calibration experiments or simulations.

关键词： uranium enrichment photonuclear reaction particle Monte Carlo transport

Cloud and Radiation Processes Simulated by a Coupled Atmosphere-Ocean Model

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Acta meteorologica Sinica 2007年第4期21卷 397-408页

作者：汪方丁一汇徐影 Laboratory for Climate studies of Chinese Meteorological Administration National Climate Center

Using NCC/IAP T63 coupled atmosphere-ocean general circulation model （AOGCM）, two 20-yr integrations were processed, and their ability to simulate cloud and radiation was analysed in detail. The results show that the model can simulate the basic distribution of cloud cover, and however, obvious differences still exist compared with ISCCP satellite data and ERA reanalysis data. The simulated cloud cover is less in general, especially the abnormal low values in some regions of ocean. By improving the cloud cover scheme, simulated cloud cover in the eastern Pacific and Atlantic, summer hemisphere＇s oceans from subtropical to mid-latitude is considerably improved. But in the tropical Indian Ocean and West Pacific the cloud cover difference is still evident, mainly due to the deficiency of high cloud simulation in these regions resulting from deep cumulus convection. In terms of the analysis on radiation and cloud radiative forcing, we find that simulation on long wave radiation is better than short wave radiation. The simulation error of short wave radiation is caused mostly by the simulation difference in short wave radiative forcing, sea ice, and snow cover, and also by not involving aerosol＇s effect. The simulation error of long wave radiation is mainly resulting from deficiency in simulating cloud cover and underlying surface temperature. Corresponding to improvement of cloud cover, the simulated radiation （especially short wave radiation） in eastern oceans, summer hemisphere＇s oceans from subtropical to mid-latitude is remarkably improved. This also brings obvious improvement to net radiation in these regions.

关键词： AOGCM cloud and radiation cloud radiative forcing cloud cover scheme

Mapping the trends and prospects of battery cathode materials based on patent landscape

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Frontiers in Energy 2023年第6期17卷 822-832页

作者： Chen YANG Xin-Yu MU School of Japanese Culture and Economy Xi’an International Studies UniversityXi’an 710128China The Northeast Asian Research center Xi’an International Studies UniversityXi’an 710128China

Advancing portable electronics and electric vehicles is heavily dependent on the cutting-edge lithium-ion (Li-ion) battery technology, which is closely linked to the properties of cathode materials. Identifying trends and prospects of cathode materials based on patent analysis is considered a kernel to optimize and refine battery related markets. In this paper, a patent analysis is performed on 6 popular cathode materials by comprehensively considering performance comparison, development trend, annual installed capacity, technology life cycle, and distribution among regions and patent assignees. In the technology life cycle, the cathode materials majorly used in electric vehicle have entered maturity stage, while the lithium cobalt oxide (LCO) cathode that is widely used in portable electronics is still in the growth stage. In global patent distributions, China holds more than 50% of total patents. In the top 10 patent assignees of 6 cathode materials, 2 institutes are from China with the rest being Japan (6) and Republic of Korea (2), indicating that the technology of cathode materials in China is relatively scattered while cathode research is highly concentrated in Japan and Republic of Korea. Moreover, the patent distribution has to consider practical issues as well as the impacts of core patents. For example, the high cost discourages the intention of applying international patents. This paper is expected to stimulate battery research, understand technical layout of various countries, and probably forecast innovative technology breakthroughs.

关键词： patent analysis cathode batteries technology life cycle

Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar El Baba Ali Tfaily Firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian Mustroph David Gimbel Jonathan Grossberg Daniel L.Barrow Matthew F.Gary Ali M.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy